/* ── Professional Educational Design System ─────────────────────── */
:root {
  /* Core Brand Colors - More Professional */
  --primary-color: #4a5568;
  --primary-light: #718096;
  --primary-dark: #2d3748;
  --secondary-color: #3182ce;
  --accent-color: #38a169;
  
  /* Background Gradients - Subtle and Professional */
  --background-color: #f7fafc;
  --background-gradient: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
  --card-background: #ffffff;
  --card-gradient: linear-gradient(135deg, #ffffff 0%, #f7fafc 100%);
  
  /* Text Colors */
  --text-color: #2d3748;
  --text-light: #4a5568;
  --text-muted: #718096;
  
  /* UI Elements */
  --border-color: #e2e8f0;
  --border-light: #f7fafc;
  --table-header: linear-gradient(135deg, #4a5568 0%, #3182ce 100%);
  --table-row-even: #f8faff;
  
  /* Shadows & Effects - Softer */
  --shadow-sm: 0 1px 3px rgba(74, 85, 104, 0.08);
  --shadow-md: 0 4px 12px rgba(74, 85, 104, 0.1);
  --shadow-lg: 0 8px 25px rgba(74, 85, 104, 0.12);
  --shadow-xl: 0 20px 40px rgba(74, 85, 104, 0.15);
  --shadow-color: rgba(74, 85, 104, 0.1);
  
  /* Interactive Elements */
  --footer-color: linear-gradient(135deg, #4a5568 0%, #2d3748 100%);
  --footer-text: #ffffff;
  --button-text: #2d3748;
  --isomer-background: #ffffff;
  
  /* Spacing System */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-unit: var(--spacing-md);
  
  /* Border Radius */
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
  
  /* Animation Curves */
  --ease-smooth: cubic-bezier(0.175, 0.885, 0.32, 1.275);
  --ease-gentle: cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

[data-theme="dark"] {
  /* Core Brand Colors - Professional Dark */
  --primary-color: #90cdf4;
  --primary-light: #bee3f8;
  --primary-dark: #1d394d;
  --secondary-color: #68d391;
  --accent-color: #9ae6b4;
  
  /* Background Gradients */
  --background-color: #1a202c;
  --background-gradient: linear-gradient(135deg, #1a202c 0%, #2d3748 100%);
  --card-background: #2d3748;
  --card-gradient: linear-gradient(135deg, #2d3748 0%, #4a5568 100%);
  
  /* Text Colors */
  --text-color: #f7fafc;
  --text-light: #e2e8f0;
  --text-muted: #a0aec0;
  
  /* UI Elements */
  --border-color: #4a5568;
  --border-light: #2d3748;
  --table-header: linear-gradient(135deg, #90cdf4 0%, #68d391 100%);
  --table-row-even: #374151;
  
  /* Shadows & Effects */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.15);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 8px 25px rgba(0, 0, 0, 0.25);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.3);
  --shadow-color: rgba(0, 0, 0, 0.25);
  
  /* Interactive Elements */
  --footer-color: linear-gradient(135deg, #4a5568 0%, #2d3748 100%);
  --footer-text: #f7fafc;
  --button-text: #f7fafc;
  --isomer-background: #ffffff;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  transition: background-color 0.3s ease, color 0.3s ease;
}

html, body {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%; /* Prevent font scaling in landscape */
}

body {
  font-family: 'Inter', 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--background-gradient);
  color: var(--text-color);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  position: relative;
  overflow-x: hidden;
}

/* Clean background - no patterns */

h1 {
  font-size: 2rem;
  line-height: 1.2;
}

h2 {
  font-size: 1.5rem;
  line-height: 1.3;
}

h3 {
  font-size: 1.25rem;
  line-height: 1.4;
}

/* Header & Navbar */
/* ── Ultra Modern Navigation with Gradients & Animations ────────────────── */

/* Main Navigation Container */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: linear-gradient(135deg, #4a5568 0%, #2d3748 100%);
  background-size: 200% 200%;
  animation: gradientShift 12s ease infinite;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

.site-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, #3182ce 0%, #38a169 100%);
  opacity: 0;
  transition: opacity 0.5s ease;
  z-index: -1;
}

.site-header:hover::before {
  opacity: 0.3;
}

@keyframes gradientShift {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 2rem;
  height: 80px;
  max-width: 1400px;
  margin: 0 auto;
  position: relative;
}

/* Logo Section */
.logo-section {
  display: flex;
  align-items: center;
  z-index: 1001;
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 1rem;
  text-decoration: none;
  color: white;
  font-weight: 800;
  font-size: 1.75rem;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  position: relative;
  padding: 0.5rem;
  border-radius: 16px;
}

.logo-link::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(45deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
  border-radius: 16px;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.logo-link:hover::before {
  opacity: 1;
}

.logo-link:hover {
  transform: translateY(-3px) scale(1.05);
  text-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
}

.logo-image {
  width: 60px;
  height: 60px;
  border-radius: 18px;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  border: 2px solid rgba(255, 255, 255, 0.2);
}

.logo-link:hover .logo-image {
  transform: rotate(5deg) scale(1.1);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
  border-color: rgba(255, 255, 255, 0.4);
}

.logo-text {
  background: linear-gradient(135deg, #ffffff 0%, #f8f9ff 30%, #e3e8ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.5px;
  text-shadow: none;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

/* Legacy logo styles for compatibility */
.logo {
  font-size: 1.6rem;
  font-weight: bold;
  color: white;
  display: flex;
  align-items: center;
  padding: 0.5rem 0;
}

.logo a {
  display: flex;
  align-items: center;
  margin-right: 12px;
  transition: transform 0.2s ease;
  color: white;
  text-decoration: none;
}

.logo a:hover {
  transform: scale(1.05);
  color: var(--primary-light);
}

.logo img {
  width: 50px;
  height: auto;
  object-fit: contain;
}

.logo-icon {
  margin-right: 10px;
  font-size: 1.8rem;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 32px;
  height: 24px;
  background: rgba(255, 255, 255, 0.1);
  border: 2px solid rgba(255, 255, 255, 0.2);
  cursor: pointer;
  padding: 0.75rem;
  z-index: 1002;
  border-radius: 16px;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  position: relative;
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.mobile-menu-toggle:hover {
  background: rgba(255, 255, 255, 0.2);
  border-color: rgba(255, 255, 255, 0.4);
  transform: scale(1.05) translateY(-2px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.mobile-menu-toggle:active {
  transform: scale(0.95);
}

/* Enhanced floating animation */
@keyframes float {
  0%, 100% {
    transform: translateY(0px) rotate(0deg);
  }
  25% {
    transform: translateY(-2px) rotate(1deg);
  }
  50% {
    transform: translateY(-4px) rotate(0deg);
  }
  75% {
    transform: translateY(-2px) rotate(-1deg);
  }
}

.hamburger-line {
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, #ffffff, #e6f3ff, #ffffff);
  transition: all 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  transform-origin: center;
  border-radius: 3px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  position: relative;
}

.hamburger-line::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  border-radius: 3px;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.mobile-menu-toggle:hover .hamburger-line {
  background: linear-gradient(90deg, #e6f3ff, #ffffff, #e6f3ff);
  box-shadow: 0 3px 8px rgba(0, 0, 0, 0.15);
  transform: scaleY(1.1);
}

.mobile-menu-toggle:hover .hamburger-line::before {
  opacity: 1;
}

/* Enhanced active state animations */
.mobile-menu-toggle.active {
  background: rgba(255, 107, 107, 0.2);
  border-color: rgba(255, 107, 107, 0.4);
  transform: scale(1.1);
  box-shadow: 0 10px 30px rgba(255, 107, 107, 0.3);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(1) {
  transform: rotate(45deg) translate(7px, 7px);
  background: linear-gradient(90deg, #ff6b6b, #ff8e8e, #ff6b6b);
  box-shadow: 0 3px 8px rgba(255, 107, 107, 0.3);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(2) {
  opacity: 0;
  transform: scale(0) translateX(-20px);
  background: linear-gradient(90deg, #ff6b6b, #ff8e8e);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -7px);
  background: linear-gradient(90deg, #ff6b6b, #ff8e8e, #ff6b6b);
  box-shadow: 0 3px 8px rgba(255, 107, 107, 0.3);
}

/* Add pulse effect when active */
@keyframes pulse {
  0%, 100% {
    box-shadow: 0 10px 30px rgba(255, 107, 107, 0.3);
  }
  50% {
    box-shadow: 0 15px 40px rgba(255, 107, 107, 0.5);
  }
}

.mobile-menu-toggle.active {
  animation: pulse 2s ease-in-out infinite;
}

/* Navigation Container */
.nav-container {
  display: flex;
  align-items: center;
  gap: 2rem;
  flex: 1;
  justify-content: space-between;
  margin-left: 2rem;
  transition: all 0.3s var(--ease-gentle);
}

/* Add hover animation to nav container */
.navbar:hover .nav-container {
  transform: translateX(2px);
}

/* Mobile Close Button */
.mobile-close-btn {
  display: none;
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: none;
  border: none;
  cursor: pointer;
  color: white;
  z-index: 1003;
}

.mobile-close-btn:hover {
  color: var(--primary-light);
}

/* Navigation Links */
.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 1rem 1.5rem;
  text-decoration: none;
  color: rgba(255, 255, 255, 0.9);
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: 16px;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  position: relative;
  line-height: 1.3;
  overflow: hidden;
  backdrop-filter: blur(10px);
  min-height: 44px;
}

.nav-link::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s;
}

.nav-link:hover::before {
  left: 100%;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #ffffff, #f0f8ff);
  transform: translateX(-50%);
  transition: width 0.4s ease;
}

.nav-link:hover {
  background: rgba(255, 255, 255, 0.15);
  color: #ffffff;
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.nav-link:hover::after {
  width: 80%;
}

.nav-link.active {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0.15));
  color: #ffffff;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.nav-link.active::after {
  width: 100%;
  background: linear-gradient(90deg, #ffffff, #e6f3ff, #ffffff);
}

.nav-link.active:hover {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.2));
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

/* Legacy nav-links styles for compatibility */
.nav-links a {
  color: white;
  text-decoration: none;
  padding: 0.5rem 0.75rem;
  border-radius: 4px;
  font-weight: 500;
  transition: all 0.2s;
  display: block;
  text-align: center;
}

.nav-links a:hover {
  background: rgba(255, 255, 255, 0.2);
  color: var(--primary-light);
}

.nav-links a.active {
  background: rgba(255, 255, 255, 0.3);
  color: white;
  font-weight: 600;
}

.nav-icon {
  opacity: 0.9;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
  stroke-width: 2.2;
  margin-right: 2px;
  vertical-align: middle;
}

.nav-link:hover .nav-icon,
.nav-link.active .nav-icon {
  opacity: 1;
  transform: scale(1.1) rotate(5deg);
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.2));
}

/* Right Side Controls */
.nav-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
  transition: all 0.4s var(--ease-smooth);
}

/* Animate controls on navbar hover */
.navbar:hover .nav-controls {
  transform: translateY(-2px) scale(1.02);
}

/* Theme Toggle - Redesigned for Perfect Alignment */
.theme-toggle {
  display: flex;
  align-items: center;
}

.theme-switch {
  position: relative;
  display: inline-block;
  width: 60px;
  height: 32px;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  user-select: none;
}

.theme-switch:hover {
  transform: scale(1.05);
}

.theme-switch input {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}

.theme-slider {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0.05));
  border: 1.5px solid rgba(255, 255, 255, 0.2);
  border-radius: 16px;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 3px;
  overflow: hidden;
  backdrop-filter: blur(15px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1), inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

/* Toggle Circle */
.theme-slider:before {
  content: "";
  position: absolute;
  height: 24px;
  width: 24px;
  background: linear-gradient(135deg, #ffffff, #f8fafc);
  border-radius: 50%;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15), 0 1px 2px rgba(0, 0, 0, 0.1);
  z-index: 3;
  left: 3px;
  top: 3px;
  border: 1px solid rgba(255, 255, 255, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Checked State */
.theme-switch input:checked + .theme-slider {
  background: linear-gradient(135deg, #3b82f6, #1d4ed8);
  border-color: rgba(255, 255, 255, 0.3);
  box-shadow: 0 8px 32px rgba(59, 130, 246, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

.theme-switch input:checked + .theme-slider:before {
  transform: translateX(28px);
  background: linear-gradient(135deg, #1e293b, #334155);
  border-color: rgba(255, 255, 255, 0.4);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3), 0 1px 2px rgba(0, 0, 0, 0.2);
}

/* Icon Container */
.theme-icon-container {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  pointer-events: none;
}

.sun-icon-container {
  left: 6px;
}

.moon-icon-container {
  right: 6px;
}

.theme-icon {
  width: 14px;
  height: 14px;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: block;
  flex-shrink: 0;
}

.sun-icon {
  color: #f59e0b;
  opacity: 1;
  transform: scale(1) rotate(0deg);
}

.moon-icon {
  color: #e5e7eb;
  opacity: 0.4;
  transform: scale(0.8) rotate(-20deg);
}

/* Active State Icon Animations */
.theme-switch input:checked + .theme-slider .sun-icon {
  opacity: 0.3;
  transform: scale(0.8) rotate(180deg);
  color: #fbbf24;
}

.theme-switch input:checked + .theme-slider .moon-icon {
  opacity: 1;
  transform: scale(1) rotate(0deg);
  color: #fbbf24;
}

/* Dark Theme Styles */
[data-theme="dark"] .theme-slider {
  background: linear-gradient(135deg, #374151, #1f2937);
  border-color: rgba(255, 255, 255, 0.15);
}

[data-theme="dark"] .theme-slider:before {
  background: linear-gradient(135deg, #374151, #4b5563);
  border-color: rgba(255, 255, 255, 0.2);
}

[data-theme="dark"] .theme-switch input:checked + .theme-slider {
  background: linear-gradient(135deg, #3b82f6, #2563eb);
}

[data-theme="dark"] .theme-switch input:checked + .theme-slider:before {
  background: linear-gradient(135deg, #1e293b, #334155);
}

[data-theme="dark"] .sun-icon {
  color: #9ca3af;
  opacity: 0.4;
}

[data-theme="dark"] .moon-icon {
  color: #fbbf24;
  opacity: 1;
}

[data-theme="dark"] .theme-switch input:checked + .theme-slider .sun-icon {
  opacity: 0.3;
  color: #9ca3af;
}

[data-theme="dark"] .theme-switch input:checked + .theme-slider .moon-icon {
  opacity: 1;
  color: #fbbf24;
}

/* Hide navigation text and show only icons until 1400px */
@media (max-width: 1399px) {
  .nav-link span {
    display: none;
  }
  
  .nav-link {
    padding: 1rem;
    gap: 0;
    justify-content: center;
    min-width: 48px;
  }
  
  .nav-links {
    gap: 0.1rem;
  }
  
  .isomer-dropdown-trigger span,
  .calcule-dropdown-trigger span {
    display: none;
  }
  
  .isomer-dropdown-trigger span,
  .calcule-dropdown-trigger span {
    font-size: 0.7rem;
  }
  
  .isomer-dropdown-trigger,
  .calcule-dropdown-trigger {
    padding: 1rem;
    gap: 0.2rem;
    justify-content: center;
    min-width: 48px;
  }
}


@media (min-width: 900px) and (max-width: 1199px) {
  .auth-buttons {
    flex-direction: column;
    gap: 0.5rem;
    align-items: stretch;
  }
  
  .auth-btn {
    width: 100%;
    justify-content: center;
    padding: 0.75rem 1rem;
  }
}

/* Keep theme toggle at mobile size for intermediate screens */
@media (min-width: 700px) and (max-width: 1000px) {
  .theme-switch {
    width: 60px !important;
    height: 32px !important;
  }
  
  .theme-slider {
    border-radius: 16px !important;
    padding: 3px !important;
    border: 1.5px solid rgba(255, 255, 255, 0.2) !important;
  }
  
  .theme-slider:before {
    height: 24px !important;
    width: 24px !important;
    left: 3px !important;
    top: 3px !important;
  }
  
  .theme-switch input:checked + .theme-slider:before {
    transform: translateX(28px) !important;
  }
  
  .theme-icon-container {
    width: 24px !important;
    height: 24px !important;
  }
  
  .sun-icon-container {
    left: 6px !important;
  }
  
  .moon-icon-container {
    right: 6px !important;
  }
  
  .theme-icon {
    width: 14px !important;
    height: 14px !important;
  }
}

/* Show navigation text from 1400px and above */
@media (min-width: 1400px) {
  .nav-link span {
    display: inline;
  }
  
  .nav-link {
    padding: 1rem 1.5rem;
    gap: 0.6rem;
    justify-content: flex-start;
  }
  
  .nav-links {
    gap: 0.25rem;
  }
  
  .isomer-dropdown-trigger span,
  .calcule-dropdown-trigger span {
    display: inline;
  }
  
  .isomer-dropdown-trigger span,
  .calcule-dropdown-trigger span {
    font-size: 0.8rem;
  }
  
  .isomer-dropdown-trigger,
  .calcule-dropdown-trigger {
    padding: 1rem 1.5rem;
    gap: 0.3rem;
    justify-content: center;
  }
}

/* Focus styles for accessibility */
.theme-switch input:focus + .theme-slider {
  outline: 2px solid #3b82f6;
  outline-offset: 2px;
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  .theme-switch,
  .theme-slider,
  .theme-slider:before,
  .theme-icon {
    transition: none;
  }
}

/* Authentication Section */
.auth-section {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.auth-buttons {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.auth-btn {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1.5rem;
  border: none;
  border-radius: 14px;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  text-decoration: none;
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(10px);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.auth-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  transition: left 0.6s;
}

.auth-btn:hover::before {
  left: 100%;
}

.login-btn {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
  color: white;
  border: 2px solid rgba(255, 255, 255, 0.3);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.login-btn:hover {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.1));
  color: white;
  border-color: rgba(255, 255, 255, 0.6);
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.register-btn {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0.15));
  color: white;
  border: 2px solid rgba(255, 255, 255, 0.4);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

.register-btn:hover {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.35), rgba(255, 255, 255, 0.25));
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
  border-color: rgba(255, 255, 255, 0.7);
}

/* User Dropdown */
.user-dropdown {
  position: relative;
}

.user-dropdown-trigger {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.875rem 1.25rem;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0.08));
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 16px;
  cursor: pointer;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  min-width: 160px;
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  position: relative;
  overflow: hidden;
}

.user-dropdown-trigger::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s;
}

.user-dropdown-trigger:hover::before {
  left: 100%;
}

.user-dropdown-trigger:hover {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0.15));
  border-color: rgba(255, 255, 255, 0.6);
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.user-avatar {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.4), rgba(255, 255, 255, 0.2));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  flex-shrink: 0;
  font-weight: 700;
  font-size: 1.1rem;
  border: 2px solid rgba(255, 255, 255, 0.3);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.user-dropdown-trigger:hover .user-avatar {
  transform: rotate(10deg) scale(1.1);
  border-color: rgba(255, 255, 255, 0.5);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.25);
}

.user-name {
  font-weight: 500;
  color: white;
  flex: 1;
  text-align: left;
}

.dropdown-arrow {
  color: white;
  opacity: 0.6;
  transition: all 0.4s var(--ease-smooth);
}

.user-dropdown-trigger:hover .dropdown-arrow {
  transform: rotate(180deg) scale(1.2);
  opacity: 1;
}

.user-dropdown-trigger[aria-expanded="true"] .dropdown-arrow {
  transform: rotate(180deg);
}

/* User Dropdown Menu */
.user-dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 280px;
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s ease;
  z-index: 1000;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.user-dropdown-menu.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-header {
  padding: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.user-info-display {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.user-avatar-large {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  flex-shrink: 0;
}

.user-details {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.user-greeting {
  font-size: 0.9rem;
  color: var(--text-light);
}

.user-name-display {
  font-weight: 600;
  color: var(--text-color);
  font-size: 1.1rem;
}

.dropdown-divider {
  height: 1px;
  background: var(--border-color);
  margin: 0.5rem 0;
}

.dropdown-links {
  padding: 0.5rem;
}

.dropdown-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  width: 100%;
  padding: 0.75rem 1rem;
  text-decoration: none;
  color: var(--text-color);
  border-radius: 8px;
  transition: all 0.3s ease;
  font-weight: 500;
  border: none;
  background: none;
  cursor: pointer;
  text-align: left;
}

.dropdown-link:hover {
  background: var(--card-background);
  color: var(--primary-color);
  transform: translateX(4px);
}

.logout-btn {
  color: #dc2626 !important;
  margin-top: 0.5rem;
}

.logout-btn:hover {
  background: rgba(220, 38, 38, 0.1) !important;
  color: #dc2626 !important;
}



/* ── Modern Main Content Layout ──────────────────────────────────── */
.site-main {
  padding: var(--spacing-xl) var(--spacing-lg);
  max-width: 1400px;
  width: 100%;
  margin: 0 auto;
  flex: 1 0 auto;
  position: relative;
  z-index: 1;
}

/* Hero Section Styling */
.site-main > h1 {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.3;
  letter-spacing: -0.01em;
  position: relative;
  animation: fadeInUp 0.8s var(--ease-smooth);
}

.site-main > h1::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  border-radius: 2px;
  animation: slideInBottom 1s var(--ease-smooth) 0.3s both;
}

/* Subtitle Paragraph */
.site-main > h1 + p {
  text-align: center;
  max-width: 600px;
  margin: 0 auto var(--spacing-xl) auto;
  font-size: 1.2rem;
  color: var(--text-light);
  line-height: 1.7;
  animation: fadeInUp 0.8s var(--ease-smooth) 0.2s both;
}

/* Animation Keyframes */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInBottom {
  from {
    width: 0;
    opacity: 0;
  }
  to {
    width: 80px;
    opacity: 1;
  }
}

.input-form-section {
  text-align: center;
  margin-bottom: 2rem;
}

.input-form-section h1 {
  margin-bottom: 1rem;
  color: var(--primary-color);
  font-size: clamp(1.5rem, 5vw, 2rem); /* Responsive font size */
}

.formula-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 1rem;
  align-items: center;
  width: 100%;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

.formula-form label {
  font-weight: 500;
  width: 100%;
  text-align: center;
}

/* ── Modern Form Elements ────────────────────────────────────────── */
.formula-form input[type="text"] {
  padding: var(--spacing-md) var(--spacing-lg);
  border: 2px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: 1.1rem;
  background: var(--card-gradient);
  color: var(--text-color);
  width: 100%;
  max-width: 100%;
  transition: all 0.3s var(--ease-gentle);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
  font-weight: 500;
}

.formula-form input[type="text"]:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1), var(--shadow-md);
  transform: translateY(-2px);
  background: var(--card-background);
}

.formula-form input[type="text"]::placeholder {
  color: var(--text-muted);
  font-weight: 400;
}

/* ── Professional Button System ──────────────────────────────────── */
.btn-generate {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  border: none;
  padding: var(--spacing-md) var(--spacing-xl);
  cursor: pointer;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: 0.025em;
  transition: all 0.4s var(--ease-smooth);
  width: 100%;
  max-width: 320px;
  touch-action: manipulation;
  display: block;
  margin: 0 auto;
  position: relative;
  overflow: hidden;
  text-transform: none;
  box-shadow: var(--shadow-md);
}

.btn-generate::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s;
}

.btn-generate:hover::before {
  left: 100%;
}

.btn-generate:hover {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
  transform: translateY(-3px) scale(1.02);
  box-shadow: var(--shadow-lg);
}

.note {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-top: 0.75rem;
}

.download-btn-container {
  margin-top: 1.5rem;
  width: 100%;
  display: flex;
  justify-content: center;
}

/* ── Results Section Styling ─────────────────────────────────────── */
.results-section {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
  width: 100%;
  margin-top: var(--spacing-xl);
  animation: fadeInUp 0.6s var(--ease-smooth) 0.2s both;
}

.results-section h3 {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 700;
  font-size: 1.4rem;
  margin: 0 0 var(--spacing-sm) 0;
  line-height: 1.3;
}

.results-section p {
  color: var(--text-color);
  margin: 0;
  font-size: 1.1rem;
  line-height: 1.6;
}

/* Dark theme improvements */
[data-theme="dark"] .results-section h3 {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

[data-theme="dark"] .results-section p {
  color: var(--text-color);
}

/* ── Modern Card Components ──────────────────────────────────────── */
.isomer-card {
  display: flex;
  background: var(--card-gradient);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  flex-direction: column;
  transition: all 0.4s var(--ease-smooth);
  position: relative;
  backdrop-filter: blur(10px);
}

.isomer-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color), var(--accent-color));
  transform: scaleX(0);
  transition: transform 0.4s var(--ease-smooth);
}

.isomer-card:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-light);
}

.isomer-card:hover::before {
  transform: scaleX(1);
}

.isomer-2d {
  background: linear-gradient(135deg, var(--isomer-background) 0%, #f8faff 100%);
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xl);
  min-height: 260px;
  position: relative;
  overflow: hidden;
}

.isomer-2d::after {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: conic-gradient(from 0deg, transparent, rgba(102, 126, 234, 0.03), transparent);
  animation: rotate 20s linear infinite;
  pointer-events: none;
}

@keyframes rotate {
  to {
    transform: rotate(360deg);
  }
}

.isomer-2d img {
  max-width: 100%;
  height: auto;
  object-fit: contain;
  transition: all 0.4s var(--ease-smooth);
  position: relative;
  z-index: 2;
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.1));
}

.isomer-card:hover .isomer-2d img {
  transform: scale(1.05);
}

.isomer-info {
  padding: var(--spacing-xl);
  flex: 1;
  background: var(--card-background);
  position: relative;
}

.isomer-info h3 {
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  word-break: break-word;
  font-weight: 700;
  font-size: 1.3rem;
  line-height: 1.3;
}

.btn-download-pdf {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  border: none;
  padding: var(--spacing-md) var(--spacing-xl);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.4s var(--ease-smooth);
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: 0.025em;
  display: inline-block;
  width: 100%;
  max-width: 320px;
  touch-action: manipulation;
  position: relative;
  overflow: hidden;
  text-transform: uppercase;
  box-shadow: var(--shadow-md);
}

.btn-download-pdf::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s;
}

.btn-download-pdf:hover::before {
  left: 100%;
}

.btn-download-pdf:hover {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
  transform: translateY(-3px) scale(1.02);
  box-shadow: var(--shadow-lg);
}

/* ── Google Translate Widget ───────────────────────────────────────────────── */
.translate-container {
  display: flex;
  align-items: center;
  margin-right: 1rem;
}

#google_translate_element {
  display: flex;
  align-items: center;
}

#google_translate_element .goog-te-gadget {
  font-family: 'Inter', 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif !important;
  font-size: 0.9rem !important;
  color: var(--text-color) !important;
}

#google_translate_element .goog-te-gadget .goog-te-combo {
  background: var(--card-background) !important;
  border: 1px solid var(--border-color) !important;
  border-radius: 8px !important;
  padding: 0.5rem 0.75rem !important;
  color: var(--text-color) !important;
  font-size: 0.9rem !important;
  font-weight: 500 !important;
  cursor: pointer !important;
  transition: all 0.3s ease !important;
  min-width: 120px !important;
}

#google_translate_element .goog-te-gadget .goog-te-combo:hover {
  border-color: var(--primary-color) !important;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1) !important;
}

#google_translate_element .goog-te-gadget .goog-te-combo:focus {
  outline: none !important;
  border-color: var(--primary-color) !important;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1) !important;
}

#google_translate_element .goog-te-banner-frame {
  display: none !important;
}

.goog-te-gadget img {
  display: none !important;
}

.goog-te-menu-value {
  color: var(--text-color) !important;
}

.goog-te-menu-value span:first-child {
  color: var(--text-color) !important;
}

.goog-te-menu-value span:last-child {
  color: var(--text-light) !important;
}

/* Hide Google Translate attribution */
.goog-logo-link {
  display: none !important;
}

.goog-te-gadget {
  color: transparent !important;
}

.goog-te-gadget .goog-te-combo {
  margin: 0 !important;
}

/* Mobile responsive */
@media (max-width: 900px) {
  .translate-container {
    margin-right: 0.5rem;
  }
  
  #google_translate_element .goog-te-gadget .goog-te-combo {
    min-width: 100px !important;
    padding: 0.4rem 0.6rem !important;
    font-size: 0.85rem !important;
  }
}

/* Debug styles - remove after testing */
.translate-container {
  min-height: 20px !important;
  display: flex !important;
  align-items: center !important;
}

#google_translate_element {
  min-height: 20px !important;
  display: flex !important;
  align-items: center !important;
}

@media (max-width: 768px) {
  .translate-container {
    order: -1;
    margin-bottom: 0.5rem;
    width: 100%;
    justify-content: center;
  }
  
  #google_translate_element .goog-te-gadget .goog-te-combo {
    width: 100% !important;
    max-width: 200px !important;
  }
}

/* ── Modern Enhanced Footer ───────────────────────────────────────────────── */
.site-footer {
  background: linear-gradient(135deg, #000000 0%, #0a0a0a 50%, #111111 100%);
  color: #ffffff;
  padding: 0;
  margin-top: auto;
  flex-shrink: 0;
  width: 100%;
  border-top: 1px solid rgba(255, 255, 255, 0.03);
  position: relative;
  overflow: hidden;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(45deg, transparent 30%, rgba(255, 255, 255, 0.03) 50%, transparent 70%);
  animation: gradientShift 12s ease-in-out infinite;
  pointer-events: none;
}

.footer-content {
  position: relative;
  z-index: 1;
}

/* Main Footer Section */
.footer-main {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 3rem;
  padding: 4rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.footer-section {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.footer-section h4 {
  color: #ffffff;
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0;
  position: relative;
  padding-bottom: 0.75rem;
}

.footer-section h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 3px;
  background: linear-gradient(90deg, #667eea, #764ba2);
  border-radius: 2px;
}

/* Footer Brand Section */
.footer-brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1rem;
}

.footer-logo {
  width: 50px;
  height: 50px;
  border-radius: 12px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  transition: transform 0.3s ease;
}

.footer-logo:hover {
  transform: scale(1.1) rotate(5deg);
}

.footer-brand h3 {
  color: #ffffff;
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0;
  background: linear-gradient(135deg, #667eea, #764ba2);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.4);
  line-height: 1.6;
  margin: 0;
  font-size: 0.95rem;
}

/* Footer Links */
.footer-links {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-links li {
  margin: 0;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.4);
  text-decoration: none;
  font-size: 0.95rem;
  transition: all 0.3s ease;
  display: inline-block;
  position: relative;
  padding: 0.25rem 0;
}

.footer-links a::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #667eea, #764ba2);
  transition: width 0.3s ease;
}

.footer-links a:hover {
  color: #ffffff;
  transform: translateX(5px);
}

.footer-links a:hover::before {
  width: 100%;
}

/* Footer Contact */
.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: rgba(255, 255, 255, 0.4);
  font-size: 0.95rem;
  transition: all 0.3s ease;
}

.contact-item:hover {
  color: #ffffff;
  transform: translateX(5px);
}

.contact-item svg {
  color: #667eea;
  transition: all 0.3s ease;
}

.contact-item:hover svg {
  color: #764ba2;
  transform: scale(1.1);
}

/* Footer Bottom */
.footer-bottom {
  background: rgba(0, 0, 0, 0.6);
  border-top: 1px solid rgba(255, 255, 255, 0.03);
  padding: 2rem 2rem;
}

.footer-bottom-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 2rem;
}

/* Footer Copyright */
.footer-copyright {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-copyright p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  margin: 0;
}

.team-credits {
  font-size: 0.85rem !important;
  color: rgba(255, 255, 255, 0.6) !important;
}

.team-credits strong {
  color: rgba(255, 255, 255, 0.8);
  font-weight: 600;
}

/* Footer Legal Links */
.footer-legal {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.legal-link {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  font-size: 0.9rem;
  transition: all 0.3s ease;
  position: relative;
}

.legal-link:hover {
  color: #ffffff;
  transform: translateY(-2px);
}

.separator {
  color: rgba(255, 255, 255, 0.4);
  font-size: 0.8rem;
}

/* Footer Social Links */
.footer-social {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.social-link:hover {
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: #ffffff;
  transform: translateY(-3px) scale(1.1);
  box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.social-link svg {
  transition: transform 0.3s ease;
}

.social-link:hover svg {
  transform: scale(1.1);
}

/* Footer Responsive Design */
@media (max-width: 768px) {
  .footer-main {
    grid-template-columns: 1fr;
    gap: 2rem;
    padding: 3rem 1.5rem;
  }
  
  .footer-bottom-content {
    flex-direction: column;
    text-align: center;
    gap: 1.5rem;
  }
  
  .footer-legal {
    justify-content: center;
  }
  
  .footer-social {
    justify-content: center;
  }
  
  .footer-section h4 {
    text-align: center;
  }
  
  .footer-section h4::after {
    left: 50%;
    transform: translateX(-50%);
  }
  
  .footer-brand {
    align-items: center;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .footer-main {
    padding: 2rem 1rem;
  }
  
  .footer-bottom {
    padding: 1.5rem 1rem;
  }
  
  .footer-legal {
    flex-direction: column;
    gap: 0.5rem;
  }
  
  .separator {
    display: none;
  }
  
  .social-link {
    width: 35px;
    height: 35px;
  }
}

/* Newsletter Section */
.newsletter-section {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  padding: 2rem 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.newsletter-container {
  max-width: 600px;
  margin: 0 auto;
  text-align: center;
}

.newsletter-section h3 {
  color: white;
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.newsletter-section p {
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: 1.5rem;
  font-size: 1rem;
}

.newsletter-form-container {
  margin-bottom: 1rem;
}

.newsletter-form {
  margin-bottom: 0.75rem;
}

.newsletter-input-group {
  display: flex;
  gap: 0.5rem;
  max-width: 400px;
  margin: 0 auto;
  flex-wrap: wrap;
}

.newsletter-input-group input[type="email"] {
  flex: 1;
  min-width: 200px;
  padding: 0.75rem 1rem;
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: 8px;
  font-size: 1rem;
  background: rgba(255, 255, 255, 0.1);
  color: white;
  transition: all 0.3s ease;
}

.newsletter-input-group input[type="email"]::placeholder {
  color: rgba(255, 255, 255, 0.7);
}

.newsletter-input-group input[type="email"]:focus {
  outline: none;
  border-color: rgba(255, 255, 255, 0.5);
  background: rgba(255, 255, 255, 0.15);
}

.newsletter-btn {
  padding: 0.75rem 1.5rem;
  border: 2px solid white;
  border-radius: 8px;
  background: white;
  color: var(--primary-color);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  min-width: 140px;
  position: relative;
}

.newsletter-btn:hover {
  background: transparent;
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(255, 255, 255, 0.2);
}

.newsletter-btn-secondary {
  background: transparent;
  color: white;
  border-color: rgba(255, 255, 255, 0.6);
}

.newsletter-btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: white;
}

.newsletter-btn .btn-loading {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
}

.newsletter-toggle {
  margin-top: 0.75rem;
}

.newsletter-link {
  color: rgba(255, 255, 255, 0.8);
  cursor: pointer;
  text-decoration: underline;
  font-size: 0.9rem;
  transition: color 0.3s ease;
}

.newsletter-link:hover {
  color: white;
}

.newsletter-message {
  margin-top: 1rem;
  padding: 0.75rem 1rem;
  border-radius: 6px;
  font-weight: 500;
  display: none;
}

.newsletter-message.success {
  background: rgba(76, 175, 80, 0.2);
  color: #4CAF50;
  border: 1px solid rgba(76, 175, 80, 0.3);
}

.newsletter-message.error {
  background: rgba(244, 67, 54, 0.2);
  color: #f44336;
  border: 1px solid rgba(244, 67, 54, 0.3);
}

/* Footer Content */
.footer-content {
  padding: 1rem;
  background: var(--primary-dark);
}

.footer-content p,
.footer-content a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  margin: 0;
}

.footer-content a:hover {
  color: white;
  text-decoration: underline;
}

/* Mobile responsiveness for newsletter */
@media (max-width: 768px) {
  .newsletter-section {
    padding: 1.5rem 1rem;
  }
  
  .newsletter-section h3 {
    font-size: 1.3rem;
  }
  
  .newsletter-input-group {
    flex-direction: column;
    align-items: stretch;
  }
  
  .newsletter-input-group input[type="email"] {
    min-width: auto;
    margin-bottom: 0.5rem;
  }
  
  .newsletter-btn {
    width: 100%;
  }
}

/* Newsletter Admin Section */
.newsletter-status-container {
  margin-bottom: 1.5rem;
}

.newsletter-status-container .current-info {
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1rem;
}

.newsletter-status-container .current-info p {
  margin: 0.5rem 0;
  color: var(--text-color);
}

.form-actions {
  display: flex;
  gap: 1rem;
  margin-top: 1rem;
}

.form-actions .btn-admin {
  flex: 1;
}

.btn-secondary {
  background: transparent !important;
  color: var(--text-color) !important;
  border: 2px solid var(--border-color) !important;
}

.btn-secondary:hover {
  background: var(--border-color) !important;
  color: var(--text-color) !important;
}

.form-help {
  display: block;
  margin-top: 0.25rem;
  color: var(--text-light);
  font-size: 0.85rem;
  font-style: italic;
}

@media (max-width: 768px) {
  .form-actions {
    flex-direction: column;
  }
  
  .form-actions .btn-admin {
    width: 100%;
  }
}

/* Benzene Ring Animation */
/* ── Professional Loading States ─────────────────────────────────── */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(74, 85, 104, 0.9) 0%, rgba(45, 55, 72, 0.9) 100%);
  backdrop-filter: blur(25px);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  animation: fadeIn 0.4s ease;
  overflow: hidden;
}

/* Add animated background particles */
.loading-overlay::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: 
    radial-gradient(circle at 20% 50%, rgba(49, 130, 206, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(56, 161, 105, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 40% 80%, rgba(74, 85, 104, 0.1) 0%, transparent 50%);
  animation: floatingParticles 8s ease-in-out infinite;
}

@keyframes floatingParticles {
  0%, 100% {
    transform: translateY(0px) rotate(0deg);
    opacity: 0.3;
  }
  33% {
    transform: translateY(-20px) rotate(120deg);
    opacity: 0.6;
  }
  66% {
    transform: translateY(-10px) rotate(240deg);
    opacity: 0.4;
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.loading-content {
  background: var(--card-gradient);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-xl);
  text-align: center;
  box-shadow: var(--shadow-xl);
  margin: 0 var(--spacing-lg);
  max-width: 90%;
  border: 2px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(20px);
  animation: scaleIn 0.4s var(--ease-smooth);
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.8);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.benzene-container {
  width: 120px;
  height: 120px;
  margin: 0 auto;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.benzene-ring {
  width: 90px;
  height: 90px;
  position: relative;
  animation: rotate 4s linear infinite;
}

@keyframes rotate {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

/* Clear hexagon shape */
.hexagon-shape {
  width: 100%;
  height: 100%;
  position: absolute;
  top: 0;
  left: 0;
  background-color: rgba(66, 133, 244, 0.1);
  clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
  border: 2px solid var(--primary-color);
  box-sizing: border-box;
}

/* Double circle in the middle representing alternating bonds */
.benzene-ring:after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 30px;
  height: 30px;
  transform: translate(-50%, -50%);
  border: 2px dashed var(--primary-color);
  border-radius: 50%;
  opacity: 0.7;
}

/* Carbon atoms at vertices */
.carbon {
  position: absolute;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: var(--primary-color);
  box-shadow: 0 0 8px var(--primary-light);
  z-index: 2;
  transform: translate(-50%, -50%);
}

/* Position the carbon atoms at the hexagon vertices */
.carbon.c1 { top: 0%; left: 50%; }
.carbon.c2 { top: 25%; left: 93%; }
.carbon.c3 { top: 75%; left: 93%; }
.carbon.c4 { top: 100%; left: 50%; }
.carbon.c5 { top: 75%; left: 7%; }
.carbon.c6 { top: 25%; left: 7%; }

/* Pulsing effect */
@keyframes pulse {
  0% {
    transform: scale(1);
    opacity: 0.8;
  }
  50% {
    transform: scale(1.05);
    opacity: 1;
  }
  100% {
    transform: scale(1);
    opacity: 0.8;
  }
}

.hexagon-shape {
  animation: pulse 2s ease-in-out infinite;
}

.loading-text {
  margin-top: 25px;
  font-weight: 600;
  color: var(--primary-color);
  font-size: 1.2rem;
  animation: pulse 2s ease-in-out infinite;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* Enhanced benzene ring for chemistry theme */
.benzene-ring {
  position: relative;
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.2));
}

/* Add orbiting electrons */
.benzene-ring::after {
  content: '⚛';
  position: absolute;
  top: -15px;
  left: -15px;
  right: -15px;
  bottom: -15px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--secondary-color);
  animation: orbit 3s linear infinite;
  opacity: 0.7;
}

@keyframes orbit {
  0% {
    transform: rotate(0deg) translateX(50px) rotate(0deg);
  }
  100% {
    transform: rotate(360deg) translateX(50px) rotate(-360deg);
  }
}

/* Styles for masa.html and equations.html */
.result-card {
  background: var(--card-background);
  border-radius: 8px;
  box-shadow: 0 2px 10px var(--shadow-color);
  padding: 15px;
  margin-top: 20px;
  width: 100%;
}

.result-card h2 {
  color: var(--primary-color);
  margin-bottom: 1rem;
  font-size: clamp(1.25rem, 4vw, 1.5rem);
}

.mass-info {
  display: flex;
  justify-content: space-around;
  margin: 20px 0;
  flex-wrap: wrap;
  gap: 15px;
}

.mass-box {
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 15px;
  text-align: center;
  min-width: 150px;
  flex: 1;
}

.mass-value {
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: bold;
  color: var(--primary-color);
  margin-bottom: 5px;
}

.mass-label {
  color: var(--text-light);
  font-size: 0.9rem;
}

.table-container {
  overflow-x: auto;
  margin-top: 15px;
  width: 100%;
  -webkit-overflow-scrolling: touch; /* Smooth scrolling on iOS */
}

.element-table {
  width: 100%;
  border-collapse: collapse;
  border: 1px solid var(--border-color);
  min-width: 600px; /* Ensures table is scrollable on small screens */
}

.element-table th, 
.element-table td {
  padding: 8px;
  border: 1px solid var(--border-color);
  font-size: 0.9rem;
}

.element-table th {
  background: var(--table-header);
  color: white;
  font-weight: normal;
  white-space: nowrap;
}

.element-table tr:nth-child(even) {
  background-color: var(--table-row-even);
}

.element-table .symbol {
  font-weight: bold;
  color: var(--primary-color);
}

.element-table .center {
  text-align: center;
}

.element-table .right {
  text-align: right;
}

/* Form styling */
.equation-form {
  margin: 20px 0;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  width: 100%;
}

.equation-form input[type="text"] {
  padding: 10px 12px;
  width: 100%;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 16px;
  background-color: var(--card-background);
  color: var(--text-color);
  max-width: 500px;
}


/* Results display */
.balanced-equation {
  font-size: 1.1rem;
  background: var(--background-color);
  padding: 15px;
  border-radius: 6px;
  border-left: 4px solid var(--primary-color);
  margin: 20px 0;
  overflow-x: auto;
  word-break: break-word;
}

/* Masa Form Styling */
#masaForm {
  max-width: 600px;
  margin: 20px auto;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  gap: 1rem;
}

#masaForm label {
  display: block;
  margin-bottom: 0;
  font-size: 1.1rem;
  width: 100%;
}

#masaForm input {
  padding: 10px 12px;
  width: 100%;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 16px;
  background-color: var(--card-background);
  color: var(--text-color);
  max-width: 500px;
}

/* Chestionare styling */
.question-buttons button {
  width: 40px;
  height: 40px;
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  cursor: pointer;
  font-weight: 500;
  transition: all 0.2s;
  color: var(--button-text);
  margin: 0.25rem;
  touch-action: manipulation;
}

.quiz-header {
  padding: 1rem 0;
}

.btn-nav {
  background: var(--background-color);
  border: 1px solid var(--border-color);
  padding: 0.75rem 1.25rem;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 500;
  color: var(--button-text);
  touch-action: manipulation;
  min-width: 100px;
}

.btn-finalize {
  width: 100%;
  max-width: 300px;
  margin: 1.5rem auto 0 !important;
  display: block;
}

.test-cards {
  justify-content: center;
}

.test-card {
  width: 100%;
  max-width: 280px;
  margin: 0 auto;
}

.test-card h3 {
  font-size: 1.1rem;
}

/* Modal styling */
#modalContent {
  width: 90% !important;
  max-width: 350px;
}

/* Responsive adjustments */
@media (min-width: 576px) {
  /* Small tablets and large phones */
  .formula-form {
    flex-direction: row;
    flex-wrap: wrap;
  }
  
  .equation-form {
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .equation-form input[type="text"] {
    width: auto;
    flex: 1;
    margin-right: 10px;
  }
  
  .equation-form button {
    width: auto;
  }
  
  #masaForm {
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
  }
  
  #masaForm input {
    flex: 1;
    margin-right: 10px;
  }
  
  #masaForm button {
    width: auto;
  }
}

@media (min-width: 768px) {
  /* Tablets and small laptops */
  .site-main {
    padding: 2rem;
  }
  
  .isomer-card {
    flex-direction: row;
  }
  
  .isomer-2d {
    flex: 0 0 220px;
  }
  
  .isomer-info {
    padding: 1.5rem;
  }
  
  .test-cards {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
  }
}

/* Tablet and medium screens (769px to 1024px) */
@media (max-width: 1024px) and (min-width: 769px) {
  .navbar {
    padding: 0 1.5rem;
  }
  
  .nav-container {
    gap: 1.5rem;
    margin-left: 1.5rem;
  }
  
  .nav-links {
    gap: 0.25rem;
  }
  
  .nav-link {
    padding: 0.6rem 0.8rem;
    font-size: 0.9rem;
  }
  
  .nav-link span {
    display: none; /* Hide text labels on tablet, show only icons */
  }
  
  .nav-controls {
    gap: 0.75rem;
  }
  
  .theme-switch {
    width: 50px;
    height: 26px;
  }
  
  .theme-slider:before {
    height: 20px;
    width: 20px;
  }
  
  .theme-switch input:checked + .theme-slider:before {
    transform: translateX(24px);
  }
}

/* ── Page Transition Effects ─────────────────────────────────────── */
@keyframes pageLoad {
  0% {
    opacity: 0;
    transform: translateY(20px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

.site-main {
  animation: pageLoad 0.6s var(--ease-smooth);
}

/* Professional loading spinner */
.loading-spinner {
  display: inline-block;
  width: 40px;
  height: 40px;
  border: 3px solid rgba(74, 85, 104, 0.3);
  border-radius: 50%;
  border-top-color: var(--primary-color);
  animation: spin 1s ease-in-out infinite;
  margin-top: 1rem;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* ── Responsive Design Improvements ──────────────────────────────── */
@media (max-width: 900px) {
  /* Reduce animations on mobile for better performance */
  * {
    animation-duration: 0.3s !important;
  }
  
  .site-header {
    background: linear-gradient(135deg, #4a5568 0%, #2d3748 100%);
    animation: none;
  }
  
  .site-main {
    padding: var(--spacing-lg) var(--spacing-md);
  }
  
  .site-main > h1 {
    font-size: clamp(1.8rem, 8vw, 2.5rem);
  }
  
  .section {
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
  }
  
  .navbar {
    padding: 0 1rem;
    height: 70px;
  }
  
/* --- Option 2: Sliding Arrow --- */
  
  .mobile-menu-toggle {
  display: none; /* Hidden by default on desktop */
  flex-direction: column;
  justify-content: space-between;
  width: 32px;
  height: 24px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0;
  z-index: 1000;
}

.hamburger-line {
  width: 100%;
  height: 3px;
  background-color: var(--text-color);
  border-radius: 3px;
  transition: all 0.3s cubic-bezier(0.25, 1, 0.5, 1);
  /* The cubic-bezier gives it a snappy feel */
  transform-origin: left center;
}

.mobile-menu-toggle:hover .hamburger-line {
  background-color: var(--primary-color);
}

/* Active State - forms a 'back' arrow */
.mobile-menu-toggle.active .hamburger-line:nth-child(1) {
  width: 50%;
  transform: rotate(45deg) translate(2px, -3px);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(2) {
  /* This creates the long part of the arrow */
  transform: translateX(-1px);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(3) {
  width: 50%;
  transform: rotate(-45deg) translate(2px, 3px);
  }
  
  .nav-container {
    position: fixed;
    top: 0;
    right: -100%;
    height: 100vh;
    width: 85%;
    max-width: 340px;
    background: linear-gradient(180deg, #667eea 0%, #764ba2 50%, #5a4a7c 100%);
    z-index: 1000;
    flex-direction: column;
    justify-content: flex-start;
    padding: 0;
    transition: right 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    box-shadow: -10px 0 30px rgba(0, 0, 0, 0.3);
    margin-left: 0;
    gap: 0;
    overflow-y: auto;
    backdrop-filter: blur(20px);
    border-left: 1px solid rgba(255, 255, 255, 0.1);
  }
  
  .nav-container.open {
    right: 0;
  }
  
  .mobile-close-btn {
    display: block;
  }
  
  .nav-links {
    flex-direction: column;
    width: 100%;
    margin: 0;
    padding: 80px 0 20px 0;
    gap: 0;
  }
  
  .nav-item {
    width: 100%;
  }
  
  .nav-link {
    width: 100%;
    padding: 1.25rem 1.75rem;
    text-align: left;
    border-radius: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    justify-content: flex-start;
    gap: 1rem;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.05), transparent);
    margin-bottom: 2px;
    position: relative;
    overflow: hidden;
  }
  
  .nav-link::before {
    left: -100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.15), transparent);
  }
  
  .nav-link:hover {
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.05), rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0.05));
    transform: translateX(5px);
    box-shadow: 5px 0 15px rgba(0, 0, 0, 0.1);
  }
  
  .nav-link span {
    display: inline; /* Show text on mobile */
  }
  
  .nav-controls {
    flex-direction: column;
    gap: 1rem;
    padding: 1rem 1.5rem 2rem 1.5rem;
    width: 100%;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: 1rem;
  }
  
  .theme-toggle {
    width: 100%;
    justify-content: center;
  }
  
  .auth-section {
    width: 100%;
  }
  
  .auth-buttons {
    flex-direction: column;
    gap: 0.75rem;
    width: 100%;
  }
  
  .auth-btn {
    width: 100%;
    justify-content: center;
    padding: 0.75rem 1rem;
  }
  
  .user-dropdown {
    width: 100%;
  }
  
  .user-dropdown-trigger {
    width: 100%;
    justify-content: space-between;
    padding: 1rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  }
  
  .user-dropdown-menu {
    position: static;
    transform: none;
  }
  
  /* Isomer dropdown mobile styles */
  .isomer-dropdown-menu {
    position: static;
    transform: none;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    border: none;
    background: rgba(255, 255, 255, 0.1);
    margin-top: 0.5rem;
    border-radius: var(--radius-md);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
    padding: 0 var(--spacing-md);
  }
  
  .isomer-dropdown-menu.show {
    max-height: 200px;
    padding: var(--spacing-xs) var(--spacing-md);
  }
  
  .isomer-dropdown-menu .dropdown-link {
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-sm);
    margin: 0.2rem 0;
  }
  
  /* Calcule dropdown mobile styles */
  .calcule-dropdown-menu {
    position: static;
    transform: none;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    border: none;
    background: rgba(255, 255, 255, 0.1);
    margin-top: 0.5rem;
    border-radius: var(--radius-md);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
    padding: 0 var(--spacing-md);
  }
  
  .calcule-dropdown-menu.show {
    max-height: 200px;
    padding: var(--spacing-xs) var(--spacing-md);
  }
  
  .calcule-dropdown-menu .dropdown-link {
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-sm);
    margin: 0.2rem 0;
  }
  
  .user-dropdown-menu {
    box-shadow: none;
    border: none;
    border-radius: 0;
    background: rgba(255, 255, 255, 0.05);
    margin-top: 0;
    padding: 0;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transition: max-height 0.3s ease, opacity 0.3s ease, visibility 0.3s ease;
  }
  
  .user-dropdown-menu.show {
    max-height: 500px;
    opacity: 1;
    visibility: visible;
  }
  
  .dropdown-header {
    padding: 1rem 0 0.5rem 0;
    text-align: center;
  }
  
  .user-info-display {
    justify-content: center;
    gap: 1rem;
  }
  
  .dropdown-divider {
    background: rgba(255, 255, 255, 0.1);
    margin: 0.5rem 0;
  }
  
  .dropdown-links {
    padding: 0;
  }
  
  .dropdown-link {
    color: white;
    padding: 1rem 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    text-decoration: none;
    background: none;
    border-left: none;
    border-right: none;
    border-top: none;
    width: 100%;
    text-align: center;
  }
  
  .dropdown-link:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--primary-light);
    transform: none;
  }
  
  .logout-btn {
    color: #ff6b6b !important;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: 0.5rem;
  }
  
  .logout-btn:hover {
    background: rgba(255, 107, 107, 0.1) !important;
    color: #ff6b6b !important;
  }
  
  /* Menu backdrop */
  .menu-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease;
  }
  
  .menu-backdrop.show {
    opacity: 1;
    visibility: visible;
  }
  
  /* Legacy mobile menu styles for compatibility */
  .mobile-menu-btn {
    display: block;
    margin: 0;
    order: 3;
  }
  
  .mobile-menu-btn.in-menu {
    position: absolute;
    top: 15px;
    right: 15px;
    margin: 0;
    z-index: 101;
    display: block;
  }
  
  .nav-links a {
    padding: 15px 20px;
    width: 100%;
    text-align: left;
    border-radius: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  }
  
  .theme-switch-wrapper {
    margin: 20px auto;
  }
  
  /* Content adjustments for mobile */
  h1 {
    font-size: 1.5rem;
  }
  
  h2 {
    font-size: 1.3rem;
  }
  
  .element-table th, 
  .element-table td {
    padding: 6px;
    font-size: 0.8rem;
  }
  
  .quiz-nav {
    justify-content: space-between;
  }
  
  .btn-nav {
    padding: 0.6rem 1rem;
    min-width: 80px;
  }
  
  .question-buttons button {
    width: 35px;
    height: 35px;
    margin: 0.2rem;
  }
}

/* Small mobile devices (480px and below) */
@media (max-width: 480px) {
  .navbar {
    padding: 0 0.75rem;
  }
  
  .logo-link {
    font-size: 1.25rem;
    gap: 0.5rem;
  }
  
  .logo-image {
    width: 40px;
    height: 40px;
  }
  
  .nav-container {
    width: 90%;
    max-width: 280px;
  }
  
  .nav-link {
    padding: 0.875rem 1rem;
    font-size: 0.9rem;
  }
  
  .site-main {
    padding: 1rem 0.75rem;
  }
  
  .question-buttons button {
    width: 32px;
    height: 32px;
    font-size: 0.85rem;
  }
}

/* Extra small devices (375px and below) */
@media (max-width: 375px) {
  .navbar {
    padding: 0 0.5rem;
  }
  
  .logo-link {
    font-size: 1.1rem;
  }
  
  .logo-image {
    width: 36px;
    height: 36px;
  }
  
  .nav-container {
    width: 95%;
  }
  
  .nav-link {
    padding: 0.75rem 0.875rem;
    font-size: 0.85rem;
  }
  
  .site-main {
    padding: 1rem 0.5rem;
  }
  
  .question-buttons button {
    width: 30px;
    height: 30px;
    font-size: 0.8rem;
  }
  
  .logo {
    font-size: 1.4rem;
  }
  
  .nav-links a {
    padding: 0.4rem 0.6rem;
    font-size: 0.9rem;
  }
}

/* Loading state and spinner */
.loading-state {
  text-align: center;
  margin: 2rem auto;
  padding: 1rem;
}

.loading-spinner {
  display: inline-block;
  width: 50px;
  height: 50px;
  border: 4px solid rgba(0, 0, 0, 0.1);
  border-radius: 50%;
  border-top-color: var(--primary-color);
  animation: spinner 1s ease-in-out infinite;
  margin-top: 1rem;
}

@keyframes spinner {
  to {
    transform: rotate(360deg);
  }
}

.loading-message {
  text-align: center;
  color: var(--primary-color);
  font-weight: 500;
  margin: 1rem 0;
  padding: 0.5rem;
  background-color: var(--background-color);
  border-radius: 6px;
  box-shadow: 0 2px 4px var(--shadow-color);
}

/* Dark mode improvements for loading message */
[data-theme="dark"] .loading-message {
  color: #4285F4;
  background-color: #303134;
  border: 1px solid #5f6368;
}

/* General dark mode text improvements */
[data-theme="dark"] h1,
[data-theme="dark"] h2,
[data-theme="dark"] h3,
[data-theme="dark"] h4,
[data-theme="dark"] h5,
[data-theme="dark"] h6 {
  color: #ffffff !important;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
}

[data-theme="dark"] .site-main p,
[data-theme="dark"] .site-main span,
[data-theme="dark"] .site-main div {
  color: #e8eaed !important;
}



/* Fix for note text */
[data-theme="dark"] .note {
  color: #bdc1c6 !important;
}

/* Load more button */
.btn-load-more {
  background: var(--secondary-color);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 500;
  margin: 1.5rem auto;
  display: block;
  width: 100%;
  max-width: 300px;
  transition: background-color 0.3s ease;
  touch-action: manipulation;
  font-size: 1rem;
}

.btn-load-more:hover, .btn-load-more:focus {
  background-color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 8px var(--shadow-color);
}

.btn-load-more:disabled {
  background-color: var(--text-light);
  cursor: not-allowed;
  opacity: 0.7;
  transform: none;
  box-shadow: none;
}

.isomer-cards-container {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  width: 100%;
  margin-bottom: 1.5rem;
}

/* PDF styling */
.pdf-content {
  padding: 10px;
  max-width: 100%;
}

.pdf-title {
  font-size: 18px;
  font-weight: bold;
  margin-bottom: 20px;
  text-align: center;
}

.pdf-page-header {
  font-size: 14px;
  margin: 20px 0 10px 0;
  padding-bottom: 5px;
  border-bottom: 1px solid var(--border-color);
}

.pdf-page-break {
  page-break-after: always;
  margin-bottom: 20px;
  height: 1px;
}

.pdf-page {
  margin-bottom: 20px;
}

/* Make isomer cards in PDF content adapt to smaller screens */
.pdf-content .isomer-cards-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr));
  gap: 10px;
}

.pdf-content .isomer-card {
  max-width: 100%;
  display: flex;
  flex-direction: column;
}

.pdf-content .isomer-2d {
  min-height: 150px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--isomer-background);
}

.pdf-content .isomer-info h3 {
  font-size: 12px;
  word-break: break-all;
}

@media (max-width: 767px) {
  .pdf-content .isomer-cards-container {
    grid-template-columns: 1fr;
  }
  
  .pdf-content .isomer-2d {
    min-height: 120px;
  }
}

/* Progress status */
#renderStatus {
  text-align: center;
  background-color: var(--primary-light);
  color: var(--text-color);
  padding: 8px 12px;
  border-radius: 4px;
  margin: 10px auto;
  max-width: 90%;
  font-weight: 500;
  box-shadow: 0 2px 4px var(--shadow-color);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% {
    opacity: 0.8;
  }
  50% {
    opacity: 1;
  }
  100% {
    opacity: 0.8;
  }
}

/* Isomer limit message styling */
.isomer-limit-message {
  background-color: var(--primary-light);
  color: var(--text-color);
  padding: 0.75rem 1rem;
  border-radius: 4px;
  margin-bottom: 1rem;
  text-align: center;
  font-weight: 500;
  border: 1px solid var(--primary-color);
}

/* Styles for confirmation buttons in isomer generation */
.confirmation-buttons {
  display: flex;
  justify-content: center;
  gap: 1rem; /* Space between buttons */
  margin-top: 1rem;
  margin-bottom: 1rem;
}

.btn-confirm-yes,
.btn-confirm-no {
  padding: 0.6rem 1.2rem;
  font-size: 0.95rem;
  border-radius: 5px;
  cursor: pointer;
  border: none;
  font-weight: 500;
  transition: background-color 0.2s ease, transform 0.1s ease;
}

.btn-confirm-yes {
  background-color: var(--secondary-color); /* Green for 'Yes' */
  color: #fff;
}

.btn-confirm-yes:hover {
  background-color: #2a8c4a; /* Darker green */
  transform: translateY(-1px);
}

.btn-confirm-no {
  background-color: #e0e0e0; /* Light grey for 'No' */
  color: var(--text-color);
  border: 1px solid #ccc;
}

.btn-confirm-no:hover {
  background-color: #d5d5d5; /* Slightly darker grey */
  transform: translateY(-1px);
}



/* ── Section Components ──────────────────────────────────────────── */
.section {
  margin: 0 auto var(--spacing-2xl) auto;
  max-width: 900px;
  background: var(--card-gradient);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: all 0.4s var(--ease-smooth);
  position: relative;
  backdrop-filter: blur(10px);
}

.section:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.section h2 { 
  margin-top: 0;
  margin-bottom: var(--spacing-lg);
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 700;
  font-size: 1.8rem;
  line-height: 1.3;
}

/* ── Micro-Animations ────────────────────────────────────────────── */
.input-form-section {
  animation: fadeInUp 0.6s var(--ease-smooth);
}

.isomer-cards-container {
  animation: fadeInUp 0.8s var(--ease-smooth) 0.2s both;
}

.formula-form {
  animation: fadeInUp 0.6s var(--ease-smooth) 0.1s both;
}

/* Stagger animation for cards */
.isomer-card:nth-child(1) { animation-delay: 0.1s; }
.isomer-card:nth-child(2) { animation-delay: 0.2s; }
.isomer-card:nth-child(3) { animation-delay: 0.3s; }
.isomer-card:nth-child(4) { animation-delay: 0.4s; }
.isomer-card:nth-child(5) { animation-delay: 0.5s; }

.isomer-card {
  animation: fadeInUp 0.6s var(--ease-smooth) both;
}

/* Hover effects for interactive elements */
.formula-form label {
  transition: all 0.3s var(--ease-gentle);
}

.formula-form:hover label {
  color: var(--primary-color); 
  transform: translateX(2px);
}

/* Authentication Styles */
.auth-section {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: 1rem;
}

.auth-buttons {
  display: flex;
  gap: 0.5rem;
}

.auth-btn {
  background: rgba(255, 255, 255, 0.2);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.3);
  padding: 0.4rem 0.8rem;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s;
  white-space: nowrap;
}

.auth-btn:hover {
  background: rgba(255, 255, 255, 0.3);
  border-color: rgba(255, 255, 255, 0.5);
}

.user-info {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.user-welcome {
  color: #fff;
  font-size: 0.9rem;
  font-weight: 500;
}

/* Authentication Modal */
.auth-modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(3px);
}

.auth-modal-content {
  background-color: var(--card-background);
  margin: 5% auto;
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 8px 32px var(--shadow-color);
  width: 90%;
  max-width: 400px;
  max-height: 80vh;
  position: relative;
  animation: modalSlideIn 0.3s ease;
  overflow-y: auto;
}

/* Class details modal needs larger width */
#classDetailsModal .auth-modal-content {
  max-width: 600px;
  max-height: 85vh;
}

@keyframes modalSlideIn {
  from {
    opacity: 0;
    transform: translateY(-50px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.auth-close {
  color: var(--text-light);
  float: right;
  font-size: 28px;
  font-weight: bold;
  cursor: pointer;
  line-height: 1;
  position: absolute;
  right: 1rem;
  top: 1rem;
}

.auth-close:hover {
  color: var(--text-color);
}

.auth-form h2 {
  margin-bottom: 1.5rem;
  color: var(--primary-color);
  text-align: center;
}

.form-group {
  margin-bottom: 1rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--text-color);
  font-weight: 500;
}

.form-group input {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 1rem;
  background-color: var(--background-color);
  color: var(--text-color);
  transition: border-color 0.2s;
}

.form-group input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 2px rgba(66, 133, 244, 0.2);
}

.auth-submit-btn {
  width: 100%;
  background: var(--primary-color);
  color: #fff;
  border: none;
  padding: 0.75rem;
  border-radius: 6px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.3s;
  margin-top: 0.5rem;
}

.auth-submit-btn:hover {
  background: var(--primary-dark);
}

.auth-submit-btn:disabled {
  background: var(--text-light);
  cursor: not-allowed;
}

.auth-switch {
  text-align: center;
  margin-top: 1.5rem;
  color: var(--text-light);
  font-size: 0.9rem;
}

.auth-switch a {
  color: var(--primary-color);
  text-decoration: none;
}

.auth-switch a:hover {
  text-decoration: underline;
}

.auth-message {
  margin-top: 1rem;
  padding: 0.75rem;
  border-radius: 6px;
  text-align: center;
  font-size: 0.9rem;
  display: none;
}

.auth-message.error {
  background-color: #fee;
  color: #c33;
  border: 1px solid #fcc;
}

.auth-message.success {
  background-color: #efe;
  color: #363;
  border: 1px solid #cfc;
}

/* Password Requirements */
.password-requirements {
  margin-top: 0.5rem;
  padding: 0.75rem;
  background-color: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 0.85rem;
}

.requirement {
  display: flex;
  align-items: center;
  margin: 0.25rem 0;
  transition: color 0.2s ease;
}

.requirement.met {
  color: #28a745;
}

.requirement.not-met {
  color: #dc3545;
}

.req-icon {
  display: inline-block;
  width: 16px;
  margin-right: 0.5rem;
  font-weight: bold;
  text-align: center;
}

.requirement.met .req-icon {
  color: #28a745;
}

.requirement.met .req-icon::before {
  content: "✓";
}

.requirement.not-met .req-icon {
  color: #dc3545;
}

.requirement.not-met .req-icon::before {
  content: "✗";
}

/* Mobile adjustments for auth */
@media (max-width: 767px) {
  .auth-section {
    width: 100%;
    justify-content: center;
    margin: 0.5rem 0;
    order: 2; /* Place auth section after nav links */
  }
  
  .auth-btn {
    font-size: 0.8rem;
    padding: 0.3rem 0.6rem;
  }
  
  .user-welcome {
    font-size: 0.8rem;
  }
  
  .auth-modal-content {
    margin: 10% auto;
    padding: 1.5rem;
    width: 95%;
  }
}

/* Admin Page Styles */
.auth-required-message {
  text-align: center;
  margin: 2rem auto;
  padding: 2rem;
  max-width: 500px;
  background: var(--card-background);
  border-radius: 12px;
  box-shadow: 0 4px 12px var(--shadow-color);
}

.auth-required-message h1 {
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.auth-required-message p {
  margin-bottom: 1.5rem;
  color: var(--text-light);
}

.admin-content {
  max-width: 800px;
  margin: 0 auto;
}

.admin-content h1 {
  text-align: center;
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.welcome-message {
  text-align: center;
  margin-bottom: 2rem;
  padding: 1rem;
  background: var(--card-background);
  border-radius: 8px;
  border-left: 4px solid var(--primary-color);
}

.admin-section {
  background: var(--card-background);
  border-radius: 12px;
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: 0 4px 12px var(--shadow-color);
}

.admin-section h2 {
  color: var(--primary-color);
  margin-bottom: 1.5rem;
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 0.5rem;
}

.danger-section {
  border: 2px solid #dc3545;
}

.danger-section h2 {
  color: #dc3545;
  border-bottom-color: #dc3545;
}

.warning-message {
  background: #fff3cd;
  color: #856404;
  padding: 1rem;
  border-radius: 6px;
  border: 1px solid #ffeaa7;
  margin-bottom: 1.5rem;
}

[data-theme="dark"] .warning-message {
  background: #2d2111;
  color: #ffeb3b;
  border-color: #5d4e37;
}

.admin-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.btn-admin {
  background: var(--primary-color);
  color: #fff;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.3s;
  align-self: flex-start;
}

.btn-admin:hover {
  background: var(--primary-dark);
}

.btn-danger {
  background: #dc3545;
}

.btn-danger:hover {
  background: #c82333;
}

.checkbox-container {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  cursor: pointer;
  line-height: 1.4;
}

.checkbox-container input[type="checkbox"] {
  width: auto;
  margin: 0;
}

.admin-message {
  margin-top: 1rem;
  padding: 0.75rem;
  border-radius: 6px;
  text-align: center;
  font-size: 0.9rem;
  display: none;
}

.admin-message.error {
  background-color: #fee;
  color: #c33;
  border: 1px solid #fcc;
}

.admin-message.success {
  background-color: #efe;
  color: #363;
  border: 1px solid #cfc;
}

/* Mobile adjustments for admin page */
@media (max-width: 767px) {
  .admin-section {
    padding: 1.5rem;
    margin-bottom: 1.5rem;
  }
  
  .admin-content {
    padding: 0 1rem;
  }
  
  .btn-admin {
    width: 100%;
    align-self: stretch;
  }
  
  .checkbox-container {
    align-items: flex-start;
  }
}

/* History Page Styles */
.history-content {
  max-width: 1000px;
  margin: 0 auto;
}

.history-content h1 {
  text-align: center;
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.history-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 2rem;
  border-bottom: 2px solid var(--border-color);
}

.tab-button {
  background: none;
  border: none;
  padding: 1rem 1.5rem;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-light);
  border-bottom: 2px solid transparent;
  transition: all 0.2s;
}

.tab-button.active {
  color: var(--primary-color);
  border-bottom-color: var(--primary-color);
}

.tab-button:hover {
  color: var(--primary-color);
  background: rgba(66, 133, 244, 0.05);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

.tab-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.tab-header h2 {
  color: var(--primary-color);
  margin: 0;
}

.stats-summary {
  display: flex;
  gap: 1rem;
}

.stat-card {
  background: var(--card-background);
  padding: 1rem 1.5rem;
  border-radius: 8px;
  text-align: center;
  box-shadow: 0 2px 8px var(--shadow-color);
  min-width: 120px;
}

.stat-number {
  font-size: 1.8rem;
  font-weight: bold;
  color: var(--primary-color);
}

.stat-label {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-top: 0.25rem;
}

.section-divider {
  margin: 2rem 0 1rem 0;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-color);
}

.section-divider h3 {
  color: var(--primary-color);
  margin: 0;
}

.history-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.history-item {
  background: var(--card-background);
  border-radius: 12px;
  padding: 1.5rem;
  box-shadow: 0 4px 12px var(--shadow-color);
  transition: transform 0.2s, box-shadow 0.2s;
}

.history-item:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px var(--shadow-color);
}

.item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.item-header h3 {
  margin: 0;
  color: var(--primary-color);
}

.formula {
  font-family: monospace;
  font-size: 1.2rem;
  background: rgba(66, 133, 244, 0.1);
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
}

.date {
  color: var(--text-light);
  font-size: 0.9rem;
}

.item-details {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.count {
  color: var(--text-color);
  font-weight: 500;
}

.item-actions {
  display: flex;
  gap: 0.5rem;
}

.btn-small {
  padding: 0.5rem 1rem;
  border: none;
  border-radius: 6px;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background 0.2s;
  font-weight: 500;
}

.btn-regenerate {
  background: var(--secondary-color);
  color: #fff;
}

.btn-regenerate:hover {
  background: #2a8c4a;
}

.btn-download {
  background: var(--primary-color);
  color: #fff;
}

.btn-download:hover {
  background: var(--primary-dark);
}

.btn-retake {
  background: #17a2b8;
  color: #fff;
}

.btn-retake:hover {
  background: #138496;
}

/* Best Scores Styles */
.best-scores-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2rem;
}

.best-score-item {
  background: var(--card-background);
  border-radius: 12px;
  padding: 1.5rem;
  box-shadow: 0 4px 12px var(--shadow-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.quiz-info h4 {
  margin: 0 0 0.5rem 0;
  color: var(--primary-color);
}

.score-details {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.score {
  font-weight: bold;
  font-size: 1.1rem;
}

.percentage {
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  font-weight: bold;
  font-size: 0.9rem;
}

.percentage.excellent {
  background: #d4edda;
  color: #155724;
}

.percentage.good {
  background: #fff3cd;
  color: #856404;
}

.percentage.needs-improvement {
  background: #f8d7da;
  color: #721c24;
}

[data-theme="dark"] .percentage.excellent {
  background: #1e4d20;
  color: #4caf50;
}

[data-theme="dark"] .percentage.good {
  background: #3d3a00;
  color: #ffeb3b;
}

[data-theme="dark"] .percentage.needs-improvement {
  background: #4a1e1e;
  color: #f44336;
}

.quiz-stats {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  font-size: 0.9rem;
  color: var(--text-light);
}

.attempts {
  font-weight: 500;
}

.score-display {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.empty-message {
  text-align: center;
  padding: 2rem;
  color: var(--text-light);
  font-style: italic;
}

.empty-message a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
}

.empty-message a:hover {
  text-decoration: underline;
}

.loading-message {
  text-align: center;
  padding: 2rem;
  color: var(--text-light);
}

.history-message {
  margin-top: 1rem;
  padding: 0.75rem;
  border-radius: 6px;
  text-align: center;
  font-size: 0.9rem;
  display: none;
}

.history-message.error {
  background-color: #fee;
  color: #c33;
  border: 1px solid #fcc;
}

.history-message.success {
  background-color: #efe;
  color: #363;
  border: 1px solid #cfc;
}

/* Mobile adjustments for history page */
@media (max-width: 767px) {
  .tab-header {
    flex-direction: column;
    align-items: stretch;
  }
  
  .stats-summary {
    justify-content: center;
  }
  
  .stat-card {
    min-width: 100px;
  }
  
  .history-tabs {
    flex-direction: row;
    overflow-x: auto;
  }
  
  .tab-button {
    white-space: nowrap;
    padding: 0.75rem 1rem;
  }
  
  .item-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }
  
  .item-details {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .item-actions {
    width: 100%;
    justify-content: stretch;
  }
  
  .btn-small {
    flex: 1;
  }
  
  .best-score-item {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .score-details {
    width: 100%;
    justify-content: space-between;
  }
}

/* ── Stiluri pentru sistemul hibrid educațional ─────────────────── */
.smart-error, .complexity-warning, .educational-suggestions {
  background: var(--card-background);
  border: 2px solid #e74c3c;
  border-radius: 8px;
  padding: 1.5rem;
  margin: 1rem 0;
  box-shadow: 0 4px 12px var(--shadow-color);
}

.complexity-warning {
  border-color: #f39c12;
}

.educational-suggestions {
  border-color: #27ae60;
}

.smart-error h3, .complexity-warning h3, .educational-suggestions h3 {
  margin-bottom: 1rem;
  font-size: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.complexity-info {
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1rem;
  margin: 1rem 0;
}

.complexity-info ul {
  margin: 0.5rem 0 0 1.5rem;
  list-style-type: disc;
}

.complexity-info li {
  margin: 0.25rem 0;
  color: var(--text-color);
}

.complexity-buttons, .suggestions-container {
  display: flex;
  gap: 1rem;
  margin: 1rem 0;
  flex-wrap: wrap;
}

.btn-warning-continue, .btn-warning-cancel {
  padding: 0.75rem 1rem;
  border: none;
  border-radius: 6px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s ease;
  font-size: 0.9rem;
}

.btn-warning-continue {
  background: #f39c12;
  color: white;
}

.btn-warning-continue:hover {
  background: #e67e22;
  transform: translateY(-1px);
}

.btn-warning-cancel {
  background: var(--border-color);
  color: var(--text-color);
}

.btn-warning-cancel:hover {
  background: #bdc3c7;
  transform: translateY(-1px);
}

.suggestion-item {
  display: flex;
  align-items: center;
  margin: 0.5rem 0;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.suggestion-formula-btn {
  background: var(--primary-color);
  color: white;
  border: none;
  padding: 0.5rem 0.75rem;
  border-radius: 4px;
  cursor: pointer;
  font-weight: 500;
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  transition: all 0.3s ease;
  min-width: fit-content;
}

.suggestion-formula-btn:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: 0 2px 6px var(--shadow-color);
}

.suggestion-description {
  color: var(--text-light);
  font-size: 0.9rem;
  line-height: 1.4;
}

.suggestion-level {
  margin: 1rem 0;
  border-left: 4px solid transparent;
  padding-left: 1rem;
}

.suggestion-level h4 {
  margin-bottom: 0.75rem;
  font-size: 1.1rem;
}

.complexity-estimate {
  background: #fff3cd;
  border: 1px solid #ffeeba;
  border-radius: 6px;
  padding: 0.75rem;
  margin: 1rem 0;
}

[data-theme="dark"] .complexity-estimate {
  background: #2d2a24;
  border-color: #3e3a2f;
  color: #ffc107;
}

/* Responsive pentru componentele educaționale */
@media (max-width: 767px) {
  .smart-error, .complexity-warning, .educational-suggestions {
    padding: 1rem;
    margin: 0.75rem 0;
  }
  
  .complexity-buttons {
    flex-direction: column;
    gap: 0.75rem;
  }
  
  .btn-warning-continue, .btn-warning-cancel {
    width: 100%;
    padding: 0.75rem;
    text-align: center;
  }
  
  .suggestion-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.25rem;
  }
  
  .suggestion-formula-btn {
    width: 100%;
    text-align: center;
  }
  
  .suggestion-description {
    width: 100%;
    text-align: left;
  }
  
  .suggestions-container {
    flex-direction: column;
    gap: 0.5rem;
  }
  
  .complexity-info {
    padding: 0.75rem;
  }
}

/* Indicatori de complexitate în timp real */
.formula-complexity-indicator {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0.5rem 0;
  padding: 0.5rem;
  border-radius: 4px;
  font-size: 0.85rem;
  transition: all 0.3s ease;
}

.complexity-simple {
  background: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.complexity-medium {
  background: #fff3cd;
  color: #856404;
  border: 1px solid #ffeeba;
}

.complexity-complex {
  background: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

[data-theme="dark"] .complexity-simple {
  background: #1e3d32;
  color: #4caf50;
  border-color: #2e5d48;
}

[data-theme="dark"] .complexity-medium {
  background: #3d3319;
  color: #ffc107;
  border-color: #5d4e2a;
}

[data-theme="dark"] .complexity-complex {
  background: #3d1a1e;
  color: #f44336;
  border-color: #5d2a2f;
}

.complexity-icon {
  font-size: 1rem;
}

/* Animații pentru feedback vizual */
@keyframes shakeFormula {
  0%, 50%, 100% { transform: translateX(0); }
  25% { transform: translateX(-2px); }
  75% { transform: translateX(2px); }
}

.formula-error {
  animation: shakeFormula 0.5s ease-in-out;
  border-color: #e74c3c !important;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.smart-error, .complexity-warning, .educational-suggestions {
  animation: fadeInUp 0.5s ease-out;
}

/* Îmbunătățiri pentru accesibilitate */
@media (prefers-reduced-motion: reduce) {
  .smart-error, .complexity-warning, .educational-suggestions {
    animation: none;
  }
  
  .formula-error {
    animation: none;
  }
  
  .suggestion-formula-btn:hover, .btn-warning-continue:hover, .btn-warning-cancel:hover {
    transform: none;
  }
}

/* Focus pentru tastatură */
.suggestion-formula-btn:focus, .btn-warning-continue:focus, .btn-warning-cancel:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

[data-theme="dark"] .suggestion-formula-btn:focus,
[data-theme="dark"] .btn-warning-continue:focus,
[data-theme="dark"] .btn-warning-cancel:focus {
  outline-color: var(--primary-light);
}

/* Specific fixes for isomer count text and summary */
[data-theme="dark"] .isomer-summary,
[data-theme="dark"] .isomer-summary h3,
[data-theme="dark"] .isomer-summary p {
  color: #ffffff !important;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
}

[data-theme="dark"] .isomer-summary {
  background-color: #303134 !important;
  border: 1px solid #5f6368;
}

/* Google OAuth Button Styling */
.auth-divider {
  margin: 1rem 0;
  text-align: center;
  position: relative;
}

.auth-divider::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--border-color);
}

.auth-divider span {
  background: var(--background-color);
  padding: 0 1rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.google-auth-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border: 2px solid #dadce0;
  border-radius: 8px;
  background: #fff;
  color: #3c4043;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.google-auth-btn:hover {
  border-color: #c1c7cd;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
  transform: translateY(-1px);
}

.google-auth-btn:active {
  transform: translateY(0);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.google-auth-btn svg {
  flex-shrink: 0;
}

/* Dark theme support for Google button */
[data-theme="dark"] .google-auth-btn {
  background: #2d2d2d;
  border-color: #5f6368;
  color: #e8eaed;
}

[data-theme="dark"] .google-auth-btn:hover {
  border-color: #8ab4f8;
  background: #3c4043;
}

[data-theme="dark"] .auth-divider span {
  background: var(--background-color);
}

/* Class Management Styles */
.class-subsection {
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 8px;
}

.class-subsection h3 {
  color: var(--text-color);
  margin-bottom: 1rem;
  font-size: 1.2rem;
}

.class-card {
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1rem;
  box-shadow: 0 2px 4px var(--shadow-color);
}

.class-card h4 {
  color: var(--text-color);
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

.class-card p {
  color: var(--text-light);
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
}

.class-card:last-child {
  margin-bottom: 0;
}

.member-card {
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1rem;
  margin-bottom: 0.5rem;
}

.member-card h5 {
  color: var(--text-color);
  margin-bottom: 0.3rem;
  font-size: 1rem;
}

.member-card p {
  color: var(--text-light);
  margin-bottom: 0.2rem;
  font-size: 0.85rem;
}

.invitation-card {
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1rem;
  box-shadow: 0 2px 4px var(--shadow-color);
}

.invitation-card h4 {
  color: var(--text-color);
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

.invitation-card p {
  color: var(--text-light);
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
}

.invitation-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 1rem;
}

.btn-small {
  padding: 0.5rem 1rem;
  font-size: 0.85rem;
  border-radius: 4px;
}

.classes-list,
.invitations-list,
.members-list {
  max-height: 400px;
  overflow-y: auto;
}

.classes-list:empty::before,
.invitations-list:empty::before,
.members-list:empty::before {
  content: "Se încarcă...";
  color: var(--text-light);
  font-style: italic;
}

/* Role selection styles */
.form-group select {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  background: var(--card-background);
  color: var(--text-color);
  font-size: 1rem;
}

.form-group select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 2px rgba(66, 133, 244, 0.2);
}

.form-group textarea {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  background: var(--card-background);
  color: var(--text-color);
  font-size: 1rem;
  resize: vertical;
  min-height: 80px;
}

.form-group textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 2px rgba(66, 133, 244, 0.2);
}

/* Dark theme adjustments for new elements */
[data-theme="dark"] .class-card,
[data-theme="dark"] .member-card,
[data-theme="dark"] .invitation-card {
  background: var(--card-background);
  border-color: var(--border-color);
}

[data-theme="dark"] .form-group select,
[data-theme="dark"] .form-group textarea {
  background: var(--card-background);
  border-color: var(--border-color);
  color: var(--text-color);
}

[data-theme="dark"] .form-group select option {
  background: var(--card-background);
  color: var(--text-color);
}

/* Role Selection Panel Styles */
.role-selection-container {
  display: flex;
  gap: 2rem;
  margin: 2rem 0;
  justify-content: center;
}

.role-option {
  background: var(--card-background);
  border: 2px solid var(--border-color);
  border-radius: 12px;
  padding: 2rem;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  flex: 1;
  max-width: 300px;
}

.role-option:hover {
  border-color: var(--primary-color);
  box-shadow: 0 4px 12px var(--shadow-color);
  transform: translateY(-2px);
}

/* Enhanced Admin Page Action Cards - Better Mobile Responsiveness */
.admin-actions-section {
  margin: 2rem 0;
}

.admin-actions-section .stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  max-width: 100%;
}

.admin-action-card {
  background: var(--card-background);
  border-radius: 16px;
  padding: 1.5rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: all 0.3s ease;
  cursor: pointer;
  position: relative;
  overflow: hidden;
  min-height: 160px;
  display: flex;
  flex-direction: column;
}

.admin-action-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-color);
}

.action-card-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
}

.action-card-icon {
  font-size: 2rem;
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  flex-shrink: 0;
}

.action-card-title {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--text-color);
  margin: 0;
}

.action-card-content {
  flex: 1;
  margin-bottom: 1rem;
}

.action-card-description {
  color: var(--text-light);
  font-size: 0.95rem;
  line-height: 1.5;
  margin: 0;
}

.action-card-footer {
  margin-top: auto;
}

.action-card-button {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s ease;
  width: 100%;
  font-size: 0.95rem;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

.action-card-button:hover {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
  transform: translateY(-1px);
  color: white;
  text-decoration: none;
}

/* Beautiful Admin Leaderboard Table Styles */
.admin-leaderboard-table,
.leaderboard-table {
  background: var(--card-background);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
  margin-bottom: 2rem;
  position: relative;
}

.admin-table-container,
.table-container {
  overflow-x: auto;
  overflow-y: visible;
  scrollbar-width: thin;
  scrollbar-color: var(--primary-color) var(--background-color);
  position: relative;
  border-radius: 20px;
  
  /* Smooth scrolling on touch devices */
  -webkit-overflow-scrolling: touch;
  scroll-behavior: smooth;
  
  /* Shadow indicators for scroll */
  background:
    linear-gradient(to right, var(--card-background) 30%, transparent),
    linear-gradient(to left, var(--card-background) 30%, transparent),
    radial-gradient(farthest-side at 0 50%, rgba(0,0,0,0.2), transparent),
    radial-gradient(farthest-side at 100% 50%, rgba(0,0,0,0.2), transparent);
  background-position: 0 0, 100% 0, 0 0, 100% 0;
  background-repeat: no-repeat;
  background-color: var(--card-background);
  background-size: 40px 100%, 40px 100%, 14px 100%, 14px 100%;
  background-attachment: local, local, scroll, scroll;
}

.admin-table-container::-webkit-scrollbar,
.table-container::-webkit-scrollbar {
  height: 10px;
}

.admin-table-container::-webkit-scrollbar-track,
.table-container::-webkit-scrollbar-track {
  background: var(--background-color);
  border-radius: 10px;
  margin: 0 20px;
}

.admin-table-container::-webkit-scrollbar-thumb,
.table-container::-webkit-scrollbar-thumb {
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  border-radius: 10px;
  border: 2px solid var(--background-color);
  box-shadow: inset 0 0 3px rgba(0, 0, 0, 0.1);
}

.admin-table-container::-webkit-scrollbar-thumb:hover,
.table-container::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(90deg, var(--primary-dark), var(--primary-color));
  box-shadow: inset 0 0 5px rgba(0, 0, 0, 0.2);
}

.admin-table-header,
.table-header {
  background: var(--primary-color);
  color: #fff;
  padding: 1rem;
  display: grid;
  grid-template-columns: 60px 1fr 100px 100px 120px;
  gap: 1rem;
  font-weight: 600;
  align-items: center;
}

.admin-table-row,
.table-row {
  padding: 1rem;
  display: grid;
  grid-template-columns: 60px 1fr 100px 100px 120px;
  gap: 1rem;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
  transition: background 0.2s ease;
}

.admin-table-row:hover,
.table-row:hover {
  background: var(--background-color);
}

.admin-table-row:last-child,
.table-row:last-child {
  border-bottom: none;
}

.rank {
  font-weight: bold;
  font-size: 1.2rem;
  text-align: center;
}

.rank.top-3 {
  color: var(--primary-color);
}

.rank.rank-1 {
  color: #ffd700;
  font-size: 1.4rem;
}

.rank.rank-2 {
  color: #c0c0c0;
  font-size: 1.3rem;
}

.rank.rank-3 {
  color: #cd7f32;
  font-size: 1.25rem;
}

.username {
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.student-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.9rem;
  flex-shrink: 0;
}

.country {
  font-size: 0.9rem;
  color: var(--text-light);
}

.score {
  font-weight: 600;
}

.percentage {
  font-weight: 600;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  text-align: center;
}

.percentage.excellent {
  background: #d4edda;
  color: #155724;
}

.percentage.good {
  background: #fff3cd;
  color: #856404;
}

.percentage.needs-improvement {
  background: #f8d7da;
  color: #721c24;
}

.time-taken {
  font-family: monospace;
  font-size: 0.9rem;
}

.date {
  font-size: 0.9rem;
  color: var(--text-light);
}

/* Scroll indicator for mobile devices */
.scroll-indicator {
  position: absolute;
  bottom: 10px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 0.5rem 1.5rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
  z-index: 20;
  white-space: nowrap;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.scroll-indicator::before,
.scroll-indicator::after {
  content: '←';
  font-size: 1rem;
  animation: scrollHint 1.5s ease-in-out infinite;
}

.scroll-indicator::after {
  content: '→';
  animation-direction: reverse;
}

@keyframes scrollHint {
  0%, 100% { transform: translateX(0); }
  50% { transform: translateX(3px); }
}

/* Mobile responsiveness for admin tables and action cards */
@media (max-width: 900px) {
  .admin-actions-section .stats-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  
  .admin-action-card {
    min-height: 140px;
    padding: 1.25rem;
  }
  
  .action-card-icon {
    width: 40px;
    height: 40px;
    font-size: 1.5rem;
  }
  
  .action-card-title {
    font-size: 1.1rem;
  }
  
  .admin-table-header,
  .table-header,
  .admin-table-row,
  .table-row {
    grid-template-columns: 40px 1fr 80px 80px;
    gap: 0.5rem;
    font-size: 0.9rem;
  }
  
  .time-taken {
    display: none;
  }
  
  .scroll-indicator {
    opacity: 0.9;
  }
  
  .table-container:hover .scroll-indicator,
  .admin-table-container:hover .scroll-indicator {
    opacity: 0;
  }
}

@media (max-width: 600px) {
  .admin-actions-section .stats-grid {
    gap: 0.75rem;
    padding: 0 0.5rem;
  }
  
  .admin-action-card {
    min-height: 120px;
    padding: 1rem;
  }
  
  .action-card-header {
    gap: 0.75rem;
  }
  
  .action-card-icon {
    width: 36px;
    height: 36px;
    font-size: 1.25rem;
  }
  
  .action-card-title {
    font-size: 1rem;
  }
  
  .action-card-description {
    font-size: 0.9rem;
  }
  
  .action-card-button {
    padding: 0.6rem 1.25rem;
    font-size: 0.9rem;
  }
}

.role-option.selected {
  border-color: var(--primary-color);
  background: rgba(66, 133, 244, 0.1);
}

.role-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.role-option h3 {
  color: var(--text-color);
  margin-bottom: 0.5rem;
  font-size: 1.3rem;
}

.role-option p {
  color: var(--text-light);
  font-size: 0.9rem;
  line-height: 1.4;
}

/* Responsive design for role selection */
@media (max-width: 768px) {
  .role-selection-container {
    flex-direction: column;
    gap: 1rem;
  }
  
  .role-option {
    max-width: none;
  }
}

/* Dark theme adjustments */
[data-theme="dark"] .role-option {
  background: var(--card-background);
  border-color: var(--border-color);
}

[data-theme="dark"] .role-option:hover {
  border-color: var(--primary-color);
}

[data-theme="dark"] .role-option.selected {
  background: rgba(66, 133, 244, 0.2);
}

/* === LEADERBOARD STYLES - REDESIGNED === */

/* Leaderboard Container */
.leaderboard-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 2rem;
}

/* Header Section */
.leaderboard-header {
  text-align: center;
  margin-bottom: 3rem;
  padding: 2rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  border-radius: 20px;
  color: white;
  box-shadow: var(--shadow-lg);
}

.leaderboard-header h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  margin-bottom: 0.5rem;
  font-weight: 700;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.leaderboard-header p {
  font-size: 1.2rem;
  opacity: 0.9;
  margin: 0;
}

/* Personal Stats Grid */
.personal-stats {
  margin-bottom: 3rem;
}

.personal-stats h2 {
  text-align: center;
  margin-bottom: 2rem;
  color: var(--text-color);
  font-size: 1.8rem;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.stat-card {
  background: var(--card-gradient);
  border-radius: 16px;
  padding: 2rem;
  text-align: center;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-light);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.stat-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

.stat-value {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
  display: block;
}

.stat-label {
  color: var(--text-muted);
  font-size: 1rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.stat-icon {
  position: absolute;
  top: 1rem;
  right: 1rem;
  opacity: 0.1;
  width: 60px;
  height: 60px;
}

/* Controls Section */
.leaderboard-controls {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  align-items: end;
  background: var(--card-background);
  padding: 2rem;
  border-radius: 16px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
}

.control-group {
  flex: 1;
  min-width: 220px;
}

.control-group label {
  display: block;
  margin-bottom: 0.75rem;
  font-weight: 600;
  color: var(--text-color);
  font-size: 0.95rem;
}

.control-group select {
  width: 100%;
  padding: 0.875rem 1rem;
  border: 2px solid var(--border-color);
  border-radius: 12px;
  background: var(--background-color);
  color: var(--text-color);
  font-size: 1rem;
  transition: all 0.3s ease;
  appearance: none;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3e%3c/svg%3e");
  background-position: right 0.75rem center;
  background-repeat: no-repeat;
  background-size: 1.25rem;
  padding-right: 3rem;
}

.control-group select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* Tabs */
.leaderboard-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 2rem;
  background: var(--card-background);
  padding: 0.5rem;
  border-radius: 16px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
}

.tab-button {
  flex: 1;
  padding: 1rem 2rem;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.3s ease;
  position: relative;
  white-space: nowrap;
}

.tab-button:hover {
  color: var(--primary-color);
  background: rgba(59, 130, 246, 0.1);
}

.tab-button.active {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

/* Modern Table Design with Perfect Spreadsheet Scrolling */
.leaderboard-table {
  background: var(--card-background);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
  margin-bottom: 2rem;
  position: relative;
}

.table-container {
  overflow-x: auto;
  overflow-y: visible;
  scrollbar-width: thin;
  scrollbar-color: var(--primary-color) var(--background-color);
  position: relative;
  border-radius: 20px;
  
  /* Smooth scrolling on touch devices */
  -webkit-overflow-scrolling: touch;
  scroll-behavior: smooth;
  
  /* Shadow indicators for scroll */
  background:
    linear-gradient(to right, var(--card-background) 30%, transparent),
    linear-gradient(to left, var(--card-background) 30%, transparent),
    radial-gradient(farthest-side at 0 50%, rgba(0,0,0,0.2), transparent),
    radial-gradient(farthest-side at 100% 50%, rgba(0,0,0,0.2), transparent);
  background-position: 0 0, 100% 0, 0 0, 100% 0;
  background-repeat: no-repeat;
  background-color: var(--card-background);
  background-size: 40px 100%, 40px 100%, 14px 100%, 14px 100%;
  background-attachment: local, local, scroll, scroll;
}

.table-container::-webkit-scrollbar {
  height: 10px;
}

.table-container::-webkit-scrollbar-track {
  background: var(--background-color);
  border-radius: 10px;
  margin: 0 20px;
}

.table-container::-webkit-scrollbar-thumb {
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  border-radius: 10px;
  border: 2px solid var(--background-color);
  box-shadow: inset 0 0 3px rgba(0, 0, 0, 0.1);
}

.table-container::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(90deg, var(--primary-dark), var(--primary-color));
  box-shadow: inset 0 0 5px rgba(0, 0, 0, 0.2);
}

/* Scroll indicator for mobile devices */
.scroll-indicator {
  position: absolute;
  bottom: 10px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 0.5rem 1.5rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
  z-index: 20;
  white-space: nowrap;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.scroll-indicator::before,
.scroll-indicator::after {
  content: '←';
  font-size: 1rem;
  animation: scrollHint 1.5s ease-in-out infinite;
}

.scroll-indicator::after {
  content: '→';
  animation-direction: reverse;
}

@keyframes scrollHint {
  0%, 100% { transform: translateX(0); }
  50% { transform: translateX(3px); }
}

@media (max-width: 900px) {
  .scroll-indicator {
    opacity: 0.9;
  }
  
  .table-container:hover .scroll-indicator {
    opacity: 0;
  }
}

.table-content {
  min-width: 880px;
  width: 100%;
  position: relative;
}

/* Spreadsheet-style Table Header */
.table-header {
  display: grid;
  grid-template-columns: 80px 1fr 120px 100px 120px 120px 140px;
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  font-weight: 700;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  position: sticky;
  top: 0;
  z-index: 10;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
  gap: 0;
  grid-auto-flow: column;
  overflow: hidden;
}

.table-header .header-item {
  padding: 1.75rem 1rem;
  text-align: center;
  border-right: 1px solid rgba(255, 255, 255, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  position: relative;
  box-sizing: border-box;
  white-space: nowrap;
  overflow: hidden;
}

.table-header .header-item:last-child {
  border-right: none;
}

.table-header .header-item::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60%;
  height: 2px;
  background: rgba(255, 255, 255, 0.3);
  border-radius: 1px;
}

.table-header .header-item:first-child::before {
  background: linear-gradient(90deg, #FFD700, #FFA500);
}

/* Spreadsheet-style Table Rows */
.table-row {
  display: grid;
  grid-template-columns: 80px 1fr 120px 100px 120px 120px 140px;
  align-items: center;
  border-bottom: 1px solid var(--border-light);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  background: var(--background-color);
  position: relative;
  min-height: 70px;
  gap: 0;
  grid-auto-flow: column;
  overflow: hidden;
}

.table-row:hover {
  background: var(--card-background);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
  z-index: 5;
}

.table-row:last-child {
  border-bottom: none;
}

.table-row > div {
  padding: 1.5rem 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  box-sizing: border-box;
  border-right: 1px solid var(--border-light);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.table-row > div:last-child {
  border-right: none;
}

.table-row .username {
  justify-content: flex-start;
  gap: 0.75rem;
}

/* Individual cell styling */
.table-row .rank {
  font-weight: 800;
  font-size: 1.2rem;
  position: relative;
}

.table-row .rank.rank-1 {
  color: #FFD700;
  background: linear-gradient(135deg, #FFD700, #FFA500);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.table-row .rank.rank-2 {
  color: #C0C0C0;
}

.table-row .rank.rank-3 {
  color: #CD7F32;
}

.table-row .rank.rank-1::before,
.table-row .rank.rank-2::before,
.table-row .rank.rank-3::before {
  content: '';
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  z-index: -1;
}

.table-row .rank.rank-1::before {
  background: radial-gradient(circle, rgba(255, 215, 0, 0.2), transparent);
}

.table-row .rank.rank-2::before {
  background: radial-gradient(circle, rgba(192, 192, 192, 0.2), transparent);
}

.table-row .rank.rank-3::before {
  background: radial-gradient(circle, rgba(205, 127, 50, 0.2), transparent);
}

.table-row .username {
  font-weight: 600;
  color: var(--text-color);
}

.student-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 1.1rem;
  flex-shrink: 0;
}

.table-row .country {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.table-row .score {
  font-weight: 700;
  color: var(--primary-color);
  font-size: 1.1rem;
}

.table-row .percentage {
  font-weight: 700;
  font-size: 0.9rem;
  padding: 0.5rem 1rem;
  border-radius: 20px;
  min-width: 60px;
}

.table-row .percentage.excellent {
  background: linear-gradient(135deg, #10B981, #059669);
  color: white;
}

.table-row .percentage.good {
  background: linear-gradient(135deg, #F59E0B, #D97706);
  color: white;
}

.table-row .percentage.needs-improvement {
  background: linear-gradient(135deg, #EF4444, #DC2626);
  color: white;
}

.table-row .time-taken,
.table-row .date {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Special handling for username to prevent wrapping */
.table-row .username span {
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 120px;
  display: inline-block;
  vertical-align: middle;
  white-space: nowrap;
}

/* === ADMIN PAGE STYLES === */

/* Modern Admin Header */
.admin-header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 4rem 2rem;
  text-align: center;
  margin-bottom: 3rem;
  border-radius: 0 0 30px 30px;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

.admin-header::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: conic-gradient(from 0deg, transparent, rgba(255, 255, 255, 0.1), transparent);
  animation: rotate 20s linear infinite;
  pointer-events: none;
}

.admin-header-content {
  position: relative;
  z-index: 2;
}

.admin-header h1 {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 800;
  margin-bottom: 1rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.admin-header-description {
  font-size: 1.2rem;
  opacity: 0.95;
  max-width: 700px;
  margin: 0 auto;
  line-height: 1.6;
}

.admin-username-highlight {
  color: #ffd700;
  font-weight: 700;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

/* Admin Dashboard Container */
.admin-dashboard {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Auth Required Styling */
.auth-required-container {
  text-align: center;
  padding: 4rem 2rem;
  max-width: 500px;
  margin: 4rem auto;
  background: var(--card-gradient);
  border-radius: 20px;
  box-shadow: var(--shadow-lg);
}

.auth-required-icon {
  font-size: 4rem;
  margin-bottom: 2rem;
  animation: pulse 2s infinite;
}

.admin-login-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  border: none;
  border-radius: 12px;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  margin-top: 1.5rem;
}

.admin-login-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
}

/* Stats Section */
.admin-stats-section {
  margin-bottom: 4rem;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.stat-card {
  background: var(--card-gradient);
  padding: 2rem;
  border-radius: 16px;
  text-align: center;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-light);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  opacity: 0;
  transition: opacity 0.3s ease;
}

.stat-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
}

.stat-card:hover::before {
  opacity: 1;
}

.stat-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  display: block;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.stat-label {
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Admin Actions Section */
.admin-actions-section {
  margin-bottom: 4rem;
}

.admin-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.admin-action-card {
  background: var(--card-gradient);
  border-radius: 20px;
  padding: 2rem;
  text-align: center;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-light);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.admin-action-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.action-card-header {
  margin-bottom: 1.5rem;
}

.action-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
  display: block;
}

.action-card-header h3 {
  font-size: 1.4rem;
  color: var(--text-color);
  margin: 0;
  font-weight: 700;
}

.action-card-content {
  flex: 1;
  margin-bottom: 2rem;
}

.action-card-content p {
  color: var(--text-muted);
  line-height: 1.6;
  margin: 0;
}

.action-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  min-width: 180px;
  justify-content: center;
}

.action-btn.primary {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.action-btn.primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
}

.action-btn.secondary {
  background: var(--card-background);
  color: var(--text-color);
  border: 2px solid var(--border-color);
}

.action-btn.secondary:hover {
  background: var(--primary-light);
  border-color: var(--primary-color);
  color: var(--primary-color);
  transform: translateY(-2px);
}

/* Modern Sections */
.modern-section {
  margin-bottom: 4rem;
}

.section-header {
  text-align: center;
  margin-bottom: 3rem;
}

.section-title {
  font-size: 2.2rem;
  color: var(--text-color);
  margin-bottom: 1rem;
  font-weight: 700;
}

.section-description {
  color: var(--text-muted);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.6;
}

/* Modern Cards */
.modern-card {
  background: var(--card-gradient);
  border-radius: 20px;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
  margin-bottom: 2rem;
  overflow: hidden;
}

.card-header {
  padding: 2rem 2rem 1rem 2rem;
  border-bottom: 1px solid var(--border-light);
  background: linear-gradient(135deg, var(--primary-light), transparent);
}

.card-header h3 {
  margin: 0;
  font-size: 1.4rem;
  color: var(--text-color);
  font-weight: 700;
}

.card-content {
  padding: 2rem;
}

/* Modern Forms */
.modern-form {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.form-group label {
  font-weight: 600;
  color: var(--text-color);
  font-size: 1rem;
}

.form-group input,
.form-group textarea,
.form-group select {
  padding: 1rem 1.25rem;
  border: 2px solid var(--border-color);
  border-radius: 10px;
  background: var(--background-color);
  color: var(--text-color);
  font-size: 1rem;
  transition: all 0.3s ease;
  resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 1rem;
}

.modern-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  min-width: 160px;
  justify-content: center;
}

.modern-btn.primary {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.modern-btn.primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
}

.modern-btn.secondary {
  background: var(--card-background);
  color: var(--text-color);
  border: 2px solid var(--border-color);
}

.modern-btn.secondary:hover {
  background: var(--primary-light);
  border-color: var(--primary-color);
  color: var(--primary-color);
  transform: translateY(-2px);
}

.modern-btn.danger {
  background: linear-gradient(135deg, #dc2626, #b91c1c);
  color: #ffffff;
  box-shadow: 0 6px 20px rgba(220, 38, 38, 0.4);
  border: 2px solid #dc2626;
  font-weight: 700;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

.modern-btn.danger:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(220, 38, 38, 0.6);
  background: linear-gradient(135deg, #b91c1c, #991b1b);
}

/* Role Selection Styling */
.role-selection-section {
  background: var(--card-gradient);
  border-radius: 20px;
  padding: 3rem 2rem;
  margin: 3rem auto;
  max-width: 1000px;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
}

.role-selection-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.role-option {
  background: var(--background-color);
  border: 2px solid var(--border-light);
  border-radius: 16px;
  padding: 2rem;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-align: center;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.role-option:hover {
  transform: translateY(-8px);
  border-color: var(--primary-color);
  box-shadow: var(--shadow-xl);
}

.role-icon-wrapper {
  margin-bottom: 1.5rem;
}

.role-icon {
  font-size: 4rem;
  display: block;
}

.role-content {
  flex: 1;
  margin-bottom: 2rem;
}

.role-content h3 {
  font-size: 1.6rem;
  color: var(--text-color);
  margin-bottom: 1rem;
  font-weight: 700;
}

.role-content p {
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.role-features {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  text-align: left;
}

.feature {
  color: var(--success-color);
  font-size: 0.9rem;
  font-weight: 500;
}

.role-select-btn {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  border: none;
  padding: 1rem 2rem;
  border-radius: 10px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  width: 100%;
}

.role-select-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.4);
}

/* Animation Classes */
.animated-card {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.animated-card.animate {
  opacity: 1;
  transform: translateY(0);
}

/* Keyframe Animations */
@keyframes rotate {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes zoomIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* Settings Section */
.admin-settings-section {
  margin-bottom: 4rem;
}

.settings-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

/* Danger Card Styling */
.danger-card {
  border: 3px solid #dc2626;
  background: linear-gradient(135deg, #fef2f2, rgba(239, 68, 68, 0.15));
  box-shadow: 0 8px 32px rgba(220, 38, 38, 0.2);
}

.danger-header {
  background: linear-gradient(135deg, rgba(220, 38, 38, 0.2), rgba(239, 68, 68, 0.1));
  border-bottom-color: #dc2626;
}

.danger-header h2 {
  color: #000000 !important;
  font-weight: 700;
  text-shadow: 0 1px 2px rgba(255, 255, 255, 0.8);
}

.warning-message {
  background: rgba(239, 68, 68, 0.2);
  border: 2px solid #dc2626;
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  color: #000000;
  font-weight: 600;
  box-shadow: 0 4px 12px rgba(220, 38, 38, 0.15);
}

.info-message {
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid var(--primary-light);
  border-radius: 8px;
  padding: 1rem;
  color: var(--primary-color);
  font-weight: 500;
}

.current-info {
  background: var(--primary-light);
  border-radius: 8px;
  padding: 1rem;
  margin-bottom: 1.5rem;
  border-left: 4px solid var(--primary-color);
}

.current-info p {
  margin: 0.25rem 0;
  color: var(--text-color);
}

.form-help {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-top: 0.25rem;
}

/* Checkbox Styling */
.checkbox-container {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  cursor: pointer;
  font-size: 0.95rem;
  line-height: 1.5;
}

.checkbox-container input[type="checkbox"] {
  display: none;
}

.checkmark {
  width: 20px;
  height: 20px;
  background: var(--background-color);
  border: 2px solid var(--border-color);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
  flex-shrink: 0;
  margin-top: 2px;
}

.checkbox-container input[type="checkbox"]:checked + .checkmark {
  background: var(--primary-color);
  border-color: var(--primary-color);
}

.checkbox-container input[type="checkbox"]:checked + .checkmark::after {
  content: '✓';
  color: white;
  font-weight: bold;
  font-size: 12px;
}

.checkbox-container:hover .checkmark {
  border-color: var(--primary-color);
}

/* Password Requirements Styling */
.password-requirements {
  margin-top: 0.75rem;
  padding: 1rem;
  background: var(--background-color);
  border-radius: 8px;
  border: 1px solid var(--border-light);
}

.requirement {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
  font-size: 0.85rem;
  transition: color 0.3s ease;
}

.requirement:last-child {
  margin-bottom: 0;
}

.requirement.met {
  color: var(--success-color);
}

.requirement.not-met {
  color: var(--error-color);
}

.req-icon {
  width: 16px;
  height: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  font-size: 10px;
  font-weight: bold;
  flex-shrink: 0;
}

.requirement.met .req-icon {
  background: var(--success-color);
  color: white;
}

.requirement.not-met .req-icon {
  background: var(--error-color);
  color: white;
}

/* Button Loading States */
.btn-loading {
  display: none;
}

.modern-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none !important;
}

/* Newsletter Status */
.newsletter-status-container {
  margin-bottom: 1.5rem;
}

#newsletterStatusText[style*="color: #4CAF50"] {
  color: var(--success-color) !important;
}

/* Responsive Design for Admin */
@media (max-width: 1200px) {
  .admin-cards-grid {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
  }
}

@media (max-width: 900px) {
  .admin-header {
    padding: 3rem 1.5rem;
  }
  
  .admin-dashboard {
    padding: 0 1rem;
  }
  
  .stats-grid {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
  }
  
  .admin-cards-grid {
    grid-template-columns: 1fr;
  }
  
  .role-selection-container {
    grid-template-columns: 1fr;
  }
  
  .settings-grid {
    grid-template-columns: 1fr;
  }
  
  .form-actions {
    flex-direction: column;
    align-items: stretch;
  }
  
  .modern-btn,
  .action-btn {
    width: 100%;
    min-width: unset;
  }
}

@media (max-width: 575px) {
  .admin-header {
    padding: 2.5rem 1rem;
  }
  
  .admin-header h1 {
    font-size: 1.8rem;
  }
  
  .admin-header-description {
    font-size: 1rem;
  }
  
  .section-title {
    font-size: 1.8rem;
  }
  
  .admin-action-card {
    padding: 1.5rem;
  }
  
  .role-option {
    padding: 1.5rem;
  }
  
  .modern-card .card-content {
    padding: 1.5rem;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .stat-card {
    padding: 1.5rem;
  }
}

@media (max-width: 480px) {
  .admin-header {
    padding: 2rem 0.75rem;
  }
  
  .section-header {
    margin-bottom: 2rem;
  }
  
  .action-icon {
    font-size: 2.5rem;
  }
  
  .stat-icon {
    font-size: 2rem;
  }
  
  .role-icon {
    font-size: 3rem;
  }
}

/* === MASA PAGE STYLES === */

/* Modern Header Section */
.masa-header {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 4rem 2rem;
  text-align: center;
  margin-bottom: 3rem;
  border-radius: 0 0 30px 30px;
  box-shadow: var(--shadow-lg);
}

.masa-header .header-content h1 {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 800;
  margin-bottom: 1rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.masa-header .header-description {
  font-size: 1.2rem;
  opacity: 0.95;
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.6;
}

/* Main Container */
.masa-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Examples Section - Using same styles as equations */
.masa-container .examples-section {
  margin-bottom: 4rem;
}

.masa-container .examples-section h2 {
  font-size: 2rem;
  color: var(--text-color);
  margin-bottom: 1rem;
  text-align: center;
}

.masa-container .examples-description {
  text-align: center;
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-bottom: 2rem;
}

.masa-container .examples-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.masa-container .example-btn {
  background: var(--card-gradient);
  border: 2px solid var(--border-light);
  border-radius: 16px;
  padding: 1.5rem;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.masa-container .example-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  transform: scaleX(0);
  transition: transform 0.3s ease;
}

.masa-container .example-btn:hover::before {
  transform: scaleX(1);
}

.masa-container .example-btn:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-color);
}

.masa-container .example-title {
  font-weight: 700;
  color: var(--text-color);
  font-size: 1rem;
}

.masa-container .example-formula {
  font-family: 'Courier New', monospace;
  color: var(--primary-color);
  font-size: 1.2rem;
  font-weight: 600;
  background: var(--background-color);
  padding: 0.5rem 1rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

/* Input Section */
.masa-container .input-section {
  background: var(--card-background);
  border-radius: 20px;
  padding: 2.5rem;
  margin-bottom: 3rem;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
}

.masa-container .input-section h2 {
  font-size: 1.8rem;
  color: var(--text-color);
  margin-bottom: 2rem;
  text-align: center;
}

.masa-container .input-container {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.masa-container .input-group {
  flex: 1;
}

.masa-container .input-label {
  display: block;
  margin-bottom: 1rem;
}

.masa-container .label-text {
  display: block;
  font-weight: 700;
  color: var(--text-color);
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
}

.masa-container .label-hint {
  display: block;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-style: italic;
}

.masa-container .input-wrapper {
  position: relative;
  align-items: center;
}

.masa-container .formula-input {
  width: 100%;
  padding: 1.25rem 1.5rem;
  font-size: 1.1rem;
  border: 2px solid var(--border-color);
  border-radius: 12px;
  background: var(--background-color);
  color: var(--text-color);
  font-family: 'Courier New', monospace;
  transition: all 0.3s ease;
  box-sizing: border-box;
}

.masa-container .formula-input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.masa-container .button-group {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

.masa-container .calculate-btn {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.masa-container .calculate-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
}

/* Results Section Enhancements */
.masa-container .result-section {
  margin-top: 3rem;
}

.masa-container .result-card {
  background: var(--card-gradient);
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
  position: relative;
  overflow: hidden;
}

.masa-container .result-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(90deg, var(--success-color), var(--primary-color));
}

.masa-container .result-card h2 {
  color: var(--text-color);
  font-size: 1.8rem;
  margin-bottom: 1.5rem;
  text-align: center;
}

.masa-container .mass-info {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.masa-container .mass-box {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 2rem;
  border-radius: 16px;
  text-align: center;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.masa-container .mass-box::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: conic-gradient(from 0deg, transparent, rgba(255, 255, 255, 0.1), transparent);
  animation: rotate 10s linear infinite;
  pointer-events: none;
}

.masa-container .mass-value {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  position: relative;
  z-index: 2;
}

.masa-container .mass-label {
  font-size: 1rem;
  opacity: 0.9;
  font-weight: 500;
  position: relative;
  z-index: 2;
}

.masa-container .result-card h3 {
  color: var(--text-color);
  font-size: 1.4rem;
  margin: 2rem 0 1rem 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.masa-container .result-card h3::before {
  content: '📊';
  font-size: 1.2rem;
}

/* Mobile Responsiveness for Masa Page */
@media (max-width: 900px) {
  .masa-header {
    padding: 3rem 1.5rem;
  }
  
  .masa-container {
    padding: 0 1rem;
  }
  
  .masa-container .examples-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  
  .masa-container .example-btn {
    padding: 1.25rem;
  }
  
  .masa-container .input-section {
    padding: 2rem 1.5rem;
  }
  
  .masa-container .button-group {
    flex-direction: column;
    align-items: stretch;
  }
  
  .masa-container .calculate-btn,
  .masa-container .random-btn {
    justify-content: center;
    padding: 1.25rem 2rem;
  }
  
  .masa-container .result-card {
    padding: 2rem 1.5rem;
  }
  
  .masa-container .mass-info {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
}

@media (max-width: 575px) {
  .masa-container .formula-input {
    font-size: 1rem;
    padding: 1.5rem 1.25rem;
  }
  
  .masa-container .button-group {
    flex-direction: column;
    gap: 1rem;
    width: 100%;
  }
  
  .masa-container .clear-btn.mobile-clear-btn {
    order: -1;
    width: 100%;
    max-width: none;
    padding: 1.25rem;
    margin-bottom: 0.5rem;
    border: 2px solid var(--error-color);
    background: var(--card-background);
    color: var(--error-color);
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    position: static;
  }
  
  .masa-container .clear-btn.mobile-clear-btn:hover {
    background: var(--error-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
  }
  
  .masa-container .calculate-btn,
  .masa-container .random-btn {
    width: 100%;
    max-width: none;
    padding: 1.25rem;
  }
}

@media (max-width: 480px) {
  .masa-header {
    padding: 2.5rem 1rem;
  }
  
  .masa-header .header-content h1 {
    font-size: 1.8rem;
  }
  
  .masa-header .header-description {
    font-size: 1rem;
  }
  
  .masa-container .examples-section h2 {
    font-size: 1.6rem;
  }
  
  .masa-container .input-section h2 {
    font-size: 1.5rem;
  }
  
  .masa-container .result-card {
    padding: 1.5rem 1rem;
  }
}

/* === EQUATIONS PAGE STYLES === */

/* Modern Header Section */
.equations-header {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 4rem 2rem;
  text-align: center;
  margin-bottom: 3rem;
  border-radius: 0 0 30px 30px;
  box-shadow: var(--shadow-lg);
}

.header-content h1 {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  font-weight: 800;
  margin-bottom: 1rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.header-description {
  font-size: 1.2rem;
  opacity: 0.95;
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.6;
}

/* Main Container */
.equations-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Examples Section */
.examples-section {
  margin-bottom: 4rem;
}

.examples-section h2 {
  font-size: 2rem;
  color: var(--text-color);
  margin-bottom: 1rem;
  text-align: center;
}

.examples-description {
  text-align: center;
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-bottom: 2rem;
}

.examples-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.example-btn {
  background: var(--card-gradient);
  border: 2px solid var(--border-light);
  border-radius: 16px;
  padding: 1.5rem;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.example-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  transform: scaleX(0);
  transition: transform 0.3s ease;
}

.example-btn:hover::before {
  transform: scaleX(1);
}

.example-btn:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-color);
}

.example-title {
  font-weight: 700;
  color: var(--text-color);
  font-size: 1.1rem;
}

.example-formula {
  font-family: 'Courier New', monospace;
  color: var(--primary-color);
  font-size: 1rem;
  font-weight: 600;
  background: var(--background-color);
  padding: 0.5rem 1rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

/* Input Section */
.input-section {
  background: var(--card-background);
  border-radius: 20px;
  padding: 2.5rem;
  margin-bottom: 3rem;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
}

.input-section h2 {
  font-size: 1.8rem;
  color: var(--text-color);
  margin-bottom: 2rem;
  text-align: center;
}

.input-container {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.input-group {
  flex: 1;
}

.input-label {
  display: block;
  margin-bottom: 1rem;
}

.label-text {
  display: block;
  font-weight: 700;
  color: var(--text-color);
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
}

.label-hint {
  display: block;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-style: italic;
}

.input-wrapper {
  position: relative;
  align-items: center;
}

.equation-input {
  width: 100%;
  padding: 1.25rem 3rem 1.25rem 1.5rem;
  font-size: 1.1rem;
  border: 2px solid var(--border-color);
  border-radius: 12px;
  background: var(--background-color);
  color: var(--text-color);
  font-family: 'Courier New', monospace;
  transition: all 0.3s ease;
  box-sizing: border-box;
}

.equation-input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

  .clear-btn {
    position: absolute;
    right: 16px;
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 8px;
  border-radius: 6px;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.clear-btn:hover {
  background: var(--error-light);
  color: var(--error-color);
}

/* Hide clear button text on desktop */
.clear-btn-text {
  display: none;
}

/* Show clear button in input field on desktop */
@media (min-width: 768px) {
  .input-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
  }
  
  .input-group {
    width: 100%;
  }
  
  .input-wrapper {
    width: 100%;
  }
  .clear-btn.mobile-clear-btn {
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    background: transparent;
    border: none;
    color: var(--text-muted);
    padding: 8px;
    border-radius: 6px;
    width: auto;
    height: auto;
    min-width: unset;
    max-width: unset;
    flex: unset;
  }
  
  .clear-btn.mobile-clear-btn:hover {
    background: var(--error-light);
    color: var(--error-color);
    transform: translateY(-50%);
    box-shadow: none;
  }
  
  .clear-btn-text {
    display: none;
  }
  
  .equation-input {
    padding-right: 3rem !important;
    margin-left: 0 !important;
    width: 100% !important;
  }
  
  .formula-input {
    padding-right: 3rem !important;
    margin-left: 0 !important;
    width: 100% !important;
  }
}

/* Equations specific clear button styling */
.equations-container .clear-btn.mobile-clear-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 1rem 1.5rem;
  background: var(--card-background);
  color: var(--text-color);
  border: 2px solid var(--border-color);
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: static;
  transform: none;
  width: auto;
  height: auto;
  min-width: unset;
  max-width: unset;
  flex: unset;
}

.equations-container .clear-btn.mobile-clear-btn:hover {
  background: var(--background-color);
  border-color: var(--error-color);
  color: var(--error-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

  .equations-container .clear-btn-text {
    display: inline;
  }
  
  .input-hint {
    margin-top: 0.5rem;
    color: var(--text-muted);
    font-style: italic;
  }
  
  .input-hint small {
    font-size: 0.85rem;
    line-height: 1.4;
  }

/* Masa specific clear button styling */
.masa-container .clear-btn.mobile-clear-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 1rem 1.5rem;
  background: var(--card-background);
  color: var(--text-color);
  border: 2px solid var(--border-color);
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: static;
  transform: none;
  width: auto;
  height: auto;
  min-width: unset;
  max-width: unset;
  flex: unset;
}

.masa-container .clear-btn.mobile-clear-btn:hover {
  background: var(--background-color);
  border-color: var(--error-color);
  color: var(--error-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

  .masa-container .clear-btn-text {
    display: inline;
  }

/* Align input with button group on larger screens */
@media (min-width: 900px) {
  .equations-container .input-container,
  .masa-container .input-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
  }
  
  .equations-container .input-group,
  .masa-container .input-group {
    width: 100%;
  }
  
  .equations-container .input-wrapper,
  .masa-container .input-wrapper {
    width: 100%;
  }
  
  .equations-container .button-group,
  .masa-container .button-group {
    display: flex;
    gap: 1rem;
    justify-content: flex-start;
    align-items: center;
  }
  
  .equations-container .equation-input,
  .masa-container .formula-input {
    width: auto;
    min-width: 300px;
    max-width: 400px;
    margin-left: 0;
    padding-right: 1rem;
  }
  
  /* Align input field with button group */
  .equations-container .input-wrapper,
  .masa-container .input-wrapper {
    margin-left: 0;
    width: 100%;
  }
  
  /* Center button group on larger screens */
  .equations-container .button-group,
  .masa-container .button-group {
    justify-content: center;
    margin-left: 0;
    padding-left: 0;
  }
}

.button-group {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

.balance-btn,
.random-btn , .clear-btn{
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.random-btn , .balance-btn, .clear-btn{
  background: var(--card-background);
  color: var(--text-color);
  border: 2px solid var(--border-color);
}

.random-btn:hover , .balance-btn:hover { 
  background: var(--background-color);
  border-color: var(--primary-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* Results Section */
.result-section {
  margin-top: 3rem;
}

.result-card {
  background: var(--card-gradient);
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
  position: relative;
  overflow: hidden;
}

.result-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(90deg, var(--success-color), var(--primary-color));
}

.result-card h2 {
  color: var(--text-color);
  font-size: 1.8rem;
  margin-bottom: 1.5rem;
  text-align: center;
}

.balanced-equation {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 2rem;
  border-radius: 16px;
  font-family: 'Courier New', monospace;
  font-size: 1.3rem;
  font-weight: 600;
  text-align: center;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-md);
  position: relative;
}

.balanced-equation::before {
  content: '⚖️';
  position: absolute;
  top: 1rem;
  left: 1.5rem;
  font-size: 1.5rem;
  opacity: 0.8;
}

.result-card h3 {
  color: var(--text-color);
  font-size: 1.4rem;
  margin: 2rem 0 1rem 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.result-card h3::before {
  content: '📊';
  font-size: 1.2rem;
}

.table-container {
  overflow-x: auto;
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
  margin-top: 1rem;
}

.element-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
  background: var(--background-color);
}

.element-table thead {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
}

.element-table th {
  padding: 1.25rem 1rem;
  text-align: left;
  font-weight: 700;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.element-table td {
  padding: 1rem;
  border-bottom: 1px solid var(--border-light);
  vertical-align: top;
}

.element-table tbody tr:hover {
  background: var(--card-background);
}

.element-table .symbol {
  font-family: 'Courier New', monospace;
  font-weight: 700;
  color: var(--primary-color);
  font-size: 1.1rem;
}

.element-table .center {
  text-align: center;
  font-weight: 700;
  color: var(--text-color);
}

.element-table .right {
  text-align: right;
  font-weight: 600;
  color: var(--text-color);
}

/* Loading message */
.loading-message {
  background: var(--card-background);
  padding: 2rem;
  border-radius: 12px;
  text-align: center;
  color: var(--text-muted);
  font-size: 1.1rem;
  border: 2px dashed var(--border-color);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.7; }
}

/* Responsive Design for Equations Page */
@media (max-width: 900px) {
  .equations-header {
    padding: 3rem 1.5rem;
  }
  
  .equations-container {
    padding: 0 1rem;
  }
  
  .examples-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  
  .example-btn {
    padding: 1.25rem;
  }
  
  .input-section {
    padding: 2rem 1.5rem;
  }
  
  .button-group {
    flex-direction: column;
    align-items: stretch;
  }
  
  .balance-btn,
  .random-btn {
    justify-content: center;
    padding: 1.25rem 2rem;
  }
  
  .result-card {
    padding: 2rem 1.5rem;
  }
  
  .balanced-equation {
    font-size: 1.1rem;
    padding: 1.5rem;
  }
  
  .element-table {
  font-size: 0.9rem;
  }
  
  .element-table th,
  .element-table td {
    padding: 0.75rem 0.5rem;
  }
}

/* Mobile fixes for input field */
@media (max-width: 575px) {
  .input-section {
    margin: 0 -1rem;
    padding: 2rem 1rem;
  }
  
  .input-container {
    width: 100%;
  }
  
  .input-group {
    width: 100%;
  }
  
  .input-wrapper {
    width: 100%;
    position: relative;
  }
  
  .equation-input {
    width: 100% !important;
    font-size: 1.2rem;
    padding: 1.75rem 1.5rem;
    min-height: 30px;
    box-sizing: border-box;
    border: 2px solid var(--border-color);
    border-radius: 12px;
  }
  
  .button-group {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    width: 100%;
    margin-top: 1rem;
  }
  
  .clear-btn.mobile-clear-btn {
    order: -1;
    width: 100%;
    max-width: none;
    padding: 1.25rem;
    margin-bottom: 0.5rem;
    border: 2px solid var(--error-color);
    background: var(--card-background);
    color: var(--error-color);
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    position: static;
  }
  
  .clear-btn.mobile-clear-btn:hover {
    background: var(--error-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
  }
  
  .clear-btn-text {
    display: inline;
  }
  
  .balance-btn,
  .random-btn {
    width: 100%;
    max-width: none;
    padding: 1.25rem;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .equations-header {
    padding: 2.5rem 1rem;
  }
  
  .header-content h1 {
    font-size: 1.8rem;
  }
  
  .header-description {
    font-size: 1rem;
  }
  
  .examples-section h2 {
    font-size: 1.6rem;
  }
  
  .input-section h2 {
    font-size: 1.5rem;
  }
  
  .input-section {
    margin: 0 -0.5rem;
    padding: 2rem 0.5rem;
    border-radius: 20px;
  }
  
  .input-container {
    width: 100%;
  }
  
  .input-group {
    width: 100%;
  }
  
  .input-wrapper {
    width: 100%;
  }
  
  .equation-input {
    width: 100% !important;
    font-size: 1.3rem;
    padding: 2rem 1.75rem;
    min-height: 32px;
    box-sizing: border-box;
    border: 2px solid var(--border-color);
    border-radius: 12px;
  }
  
  .balanced-equation {
    font-size: 1rem;
    padding: 1.25rem;
  }
  
  .result-card {
    padding: 1.5rem 1rem;
  }
}

/* Loading and Error States */
.loading {
  text-align: center;
  padding: 3rem;
  color: var(--text-muted);
  font-size: 1.1rem;
}

.error-message {
  background: linear-gradient(135deg, #FEE2E2, #FECACA);
  color: #991B1B;
  padding: 1.5rem;
  border-radius: 12px;
  margin-bottom: 2rem;
  border: 1px solid #F87171;
  text-align: center;
  font-weight: 500;
}

/* Responsive Design - Maintain Full Spreadsheet */
@media (max-width: 1200px) {
  /* Keep full table structure, enable scroll */
  .table-content {
    min-width: 880px;
  }
  
  /* Optional: slightly reduce column widths for better mobile fit */
  .table-header,
  .table-row {
    grid-template-columns: 70px 180px 110px 90px 110px 100px 120px;
  }
}

@media (max-width: 900px) {
  .leaderboard-container {
    padding: 1rem;
  }
  
  .leaderboard-header {
    padding: 1.5rem;
    margin-bottom: 2rem;
  }
  
  .stats-grid {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
  }
  
  .stat-card {
    padding: 1.5rem;
  }
  
  .leaderboard-controls {
    flex-direction: column;
    gap: 1rem;
    padding: 1.5rem;
  }
  
  .control-group {
    min-width: auto;
  }
  
  .control-group select {
    min-width: 100%;
  }
  
  .leaderboard-tabs {
    flex-direction: column;
    gap: 0.25rem;
  }
  
  .tab-button {
    padding: 0.875rem 1rem;
    text-align: center;
  }
  
  /* Ensure table stays in one line with adequate width */
  .table-content {
    min-width: 850px;
  }
  
  .table-header,
  .table-row {
    grid-template-columns: 60px 160px 95px 80px 95px 85px 105px;
    font-size: 0.85rem;
    grid-auto-flow: column;
    grid-auto-columns: max-content;
  }
  
  .table-header .header-item,
  .table-row > div {
    padding: 1rem 0.6rem;
    min-width: 0;
    overflow: hidden;
  }
  
  .student-avatar {
    width: 30px;
    height: 30px;
    font-size: 0.85rem;
  }
  
  .table-row .percentage {
    padding: 0.35rem 0.6rem;
    font-size: 0.8rem;
    min-width: 45px;
  }
  
  /* Make scroll more obvious on mobile */
  .table-container {
    box-shadow: inset -10px 0 10px -10px rgba(0,0,0,0.2),
                inset 10px 0 10px -10px rgba(0,0,0,0.2);
  }
}

@media (max-width: 480px) {
  .leaderboard-header h1 {
    font-size: 1.75rem;
  }
  
  .leaderboard-header p {
    font-size: 1rem;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .leaderboard-tabs {
    padding: 0.25rem;
  }
  
  .tab-button {
    padding: 0.75rem 0.5rem;
    font-size: 0.85rem;
  }
  
  /* Ensure table stays in one line with adequate width */
  .table-content {
    min-width: 900px;
  }
  
  .table-header,
  .table-row {
    grid-template-columns: 45px 140px 75px 70px 85px 85px 100px;
    font-size: 0.8rem;
  }
  
  .table-header .header-item,
  .table-row > div {
    padding: 0.75rem 0.4rem;
  }
  
  .table-row .username {
    gap: 0.4rem;
  }
  
  .student-avatar {
    width: 26px;
    height: 26px;
    font-size: 0.75rem;
  }
  
  .table-row .percentage {
    padding: 0.2rem 0.4rem;
    font-size: 0.7rem;
    min-width: 40px;
  }
  
  /* Enhanced scroll visibility on small screens */
  .scroll-indicator {
    opacity: 1;
    font-size: 0.7rem;
    padding: 0.4rem 1rem;
  }
  
  .table-container {
    box-shadow: inset -15px 0 15px -15px rgba(0,0,0,0.3),
                inset 15px 0 15px -15px rgba(0,0,0,0.3);
  }
}

/* Current country info styling */
.current-info {
  margin-top: 1rem;
  padding: 1rem;
  background: var(--background-color);
  border-radius: 6px;
  border: 1px solid var(--border-color);
}

/* Member and class card actions */
.member-card,
.class-card {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
}

.member-info,
.class-info {
  flex: 1;
}

.member-actions,
.class-actions {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

@media (max-width: 768px) {
  .member-card,
  .class-card {
    flex-direction: column;
    align-items: stretch;
  }
  
  .member-actions,
  .class-actions {
    flex-direction: row;
    justify-content: flex-end;
  }
}

.quick-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.quick-actions .btn-admin {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
}

.btn-admin.secondary {
  background: var(--background-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
}

/* Autocomplete styles */
.autocomplete-container {
  position: relative;
  width: 100%;
}

.autocomplete-dropdown {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-top: none;
  border-radius: 0 0 6px 6px;
  max-height: 200px;
  overflow-y: auto;
  z-index: 1000;
  display: none;
  box-shadow: 0 4px 12px var(--shadow-color);
}

.autocomplete-dropdown.show {
  display: block;
}

.autocomplete-item {
  padding: 0.75rem;
  cursor: pointer;
  border-bottom: 1px solid var(--border-color);
  transition: background 0.2s ease;
}

.autocomplete-item:last-child {
  border-bottom: none;
}

.autocomplete-item:hover,
.autocomplete-item.highlighted {
  background: var(--primary-light);
  color: #fff;
}

.autocomplete-item .username {
  font-weight: 500;
}

.autocomplete-no-results {
  padding: 0.75rem;
  color: var(--text-light);
  font-style: italic;
  text-align: center;
}

.validation-message {
  margin-top: 0.5rem;
  padding: 0.5rem;
  border-radius: 4px;
  font-size: 0.9rem;
  display: none;
}

.validation-message.error {
  background: #f8d7da !important;
  color: #721c24 !important;
  border: 1px solid #f5c6cb !important;
  display: block !important;
}

.validation-message.success {
  background: #d4edda !important;
  color: #155724 !important;
  border: 1px solid #c3e6cb !important;
  display: block !important;
}

.validation-message.warning {
  background: #fff3cd !important;
  color: #856404 !important;
  border: 1px solid #ffeaa7 !important;
  display: block !important;
}

.btn-admin.secondary:hover {
  background: var(--primary-light);
  color: #fff;
}

/* Homework Management Styles */
.homework-form {
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.5rem;
  margin: 1rem 0;
}

.homework-form h4 {
  margin: 0 0 1rem 0;
  color: var(--primary-color);
}

.form-row {
  display: flex;
  gap: 1rem;
}

.form-row .form-group {
  flex: 1;
}

.form-actions {
  display: flex;
  gap: 1rem;
  margin-top: 1rem;
}

.homework-list {
  margin-top: 1rem;
}

.homework-card {
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1rem;
  box-shadow: 0 2px 8px var(--shadow-color);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.homework-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px var(--shadow-color);
}

.homework-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.homework-title {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 0;
  color: var(--text-color);
}

.homework-quiz {
  font-size: 0.9rem;
  color: var(--text-light);
  margin: 0.25rem 0;
}

.homework-status {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  flex-wrap: wrap;
}

.status-badge {
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: 0.8rem;
  font-weight: 500;
}

.status-badge.due-soon {
  background: #fff3cd;
  color: #856404;
  border: 1px solid #ffeaa7;
}

.status-badge.overdue {
  background: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

.status-badge.active {
  background: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.homework-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-color);
  font-size: 0.9rem;
  color: var(--text-light);
}

.homework-due-date {
  font-weight: 500;
}

.homework-stats {
  display: flex;
  gap: 1rem;
}

.homework-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 1rem;
}

.btn-homework {
  padding: 0.5rem 1rem;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  transition: background 0.2s ease;
}

.btn-homework.primary {
  background: var(--primary-color);
  color: #fff;
}

.btn-homework.primary:hover {
  background: var(--primary-dark);
}

.btn-homework.secondary {
  background: var(--background-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
}

.btn-homework.secondary:hover {
  background: var(--primary-light);
  color: #fff;
}

.homework-submissions {
  margin-top: 1rem;
}

.submission-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

.submission-table th,
.submission-table td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.submission-table th {
  background: var(--background-color);
  font-weight: 600;
  color: var(--text-color);
}

.submission-rank {
  font-weight: bold;
  color: var(--primary-color);
}

.submission-rank.rank-1 {
  color: #ffd700;
}

.submission-rank.rank-2 {
  color: #c0c0c0;
}

.submission-rank.rank-3 {
  color: #cd7f32;
}

.submission-percentage {
  font-weight: 600;
}

.submission-percentage.excellent {
  color: #28a745;
}

.submission-percentage.good {
  color: #ffc107;
}

.submission-percentage.needs-improvement {
  color: #dc3545;
}

.submission-time {
  font-family: monospace;
  font-size: 0.9rem;
}

.submission-not-submitted {
  color: var(--text-light);
  font-style: italic;
}

@media (max-width: 768px) {
  .form-row {
    flex-direction: column;
  }
  
  .homework-header {
    flex-direction: column;
    gap: 1rem;
  }
  
  .homework-meta {
    flex-direction: column;
    gap: 0.5rem;
    align-items: flex-start;
  }
  
  .homework-stats {
    gap: 0.5rem;
  }
  
  .form-actions {
    flex-direction: column;
  }
  
  .submission-table {
    font-size: 0.9rem;
  }
  
  .submission-table th,
  .submission-table td {
    padding: 0.5rem;
  }
}

/* Badge Notification Styles */
.badge-notification {
  position: fixed;
  top: 20px;
  right: 20px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border-radius: 15px;
  padding: 1rem;
  box-shadow: 0 10px 30px rgba(0,0,0,0.3);
  z-index: 10000;
  max-width: 350px;
  transform: translateX(400px);
  opacity: 0;
  transition: all 0.5s ease;
  cursor: pointer;
  border: 2px solid rgba(255,255,255,0.2);
  backdrop-filter: blur(10px);
}

.badge-notification.show {
  transform: translateX(0);
  opacity: 1;
}

.badge-notification-content {
  display: flex;
  align-items: center;
  gap: 1rem;
  position: relative;
}

.badge-notification-icon {
  font-size: 3rem;
  flex-shrink: 0;
  animation: bounce 2s infinite;
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% {
    transform: translateY(0);
  }
  40% {
    transform: translateY(-10px);
  }
  60% {
    transform: translateY(-5px);
  }
}

.badge-notification-text {
  flex: 1;
}

.badge-notification-title {
  font-size: 1rem;
  font-weight: bold;
  margin-bottom: 0.25rem;
  color: #fff;
}

.badge-notification-name {
  font-size: 1.1rem;
  font-weight: bold;
  margin-bottom: 0.25rem;
  color: #f0f0f0;
}

.badge-notification-description {
  font-size: 0.9rem;
  opacity: 0.9;
  margin-bottom: 0.5rem;
  line-height: 1.3;
}

.badge-notification-points {
  font-size: 0.8rem;
  background: rgba(255,255,255,0.2);
  padding: 0.25rem 0.5rem;
  border-radius: 10px;
  display: inline-block;
  font-weight: bold;
}

.badge-notification-rarity {
  position: absolute;
  top: -8px;
  right: -8px;
  padding: 0.25rem 0.5rem;
  border-radius: 10px;
  font-size: 0.7rem;
  font-weight: bold;
  text-transform: uppercase;
  border: 2px solid rgba(255,255,255,0.3);
}

.badge-notification .rarity-common { background: #95a5a6; }
.badge-notification .rarity-uncommon { background: #27ae60; }
.badge-notification .rarity-rare { background: #3498db; }
.badge-notification .rarity-epic { background: #9b59b6; }
.badge-notification .rarity-legendary { background: #f39c12; }

/* Responsive badge notifications */
@media (max-width: 768px) {
  .badge-notification {
    top: 10px;
    right: 10px;
    left: 10px;
    max-width: none;
    transform: translateY(-100px);
  }
  
  .badge-notification.show {
    transform: translateY(0);
  }
  
  .badge-notification-content {
    gap: 0.75rem;
  }
  
  .badge-notification-icon {
    font-size: 2.5rem;
  }
}

/* ==========================================
   Quiz Builder Styles
   ========================================== */

/* Questions container */
.questions-container {
  margin-top: 1rem;
}

.question-item {
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1rem;
  position: relative;
}

.question-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.question-number {
  font-weight: bold;
  color: var(--primary-color);
  font-size: 1.1rem;
}

.remove-question-btn {
  background: #e74c3c;
  color: white;
  border: none;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.2s;
}

.remove-question-btn:hover {
  background: #c0392b;
}

.question-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.question-type-selector {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
}

.type-option {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.type-option input[type="radio"] {
  margin: 0;
}

.question-text-input {
  width: 100%;
  min-height: 80px;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-family: inherit;
  resize: vertical;
}

/* Multiple choice options */
.options-container {
  margin-top: 1rem;
}

.options-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
  font-weight: bold;
  color: var(--primary-color);
  background: rgba(66, 133, 244, 0.1);
  padding: 0.75rem;
  border-radius: 6px;
  border-left: 4px solid var(--primary-color);
}

.option-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.75rem;
  padding: 1rem;
  background: var(--background-color);
  border: 2px solid var(--border-color);
  border-radius: 8px;
  transition: all 0.2s ease;
}

.option-item:hover {
  border-color: var(--primary-color);
  box-shadow: 0 2px 8px rgba(66, 133, 244, 0.1);
}

.option-item.correct-selected {
  border-color: #27ae60;
  background: rgba(39, 174, 96, 0.05);
}

.correct-answer-section {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  min-width: 80px;
}

.correct-answer-radio {
  width: 20px;
  height: 20px;
  margin: 0;
  cursor: pointer;
  accent-color: #27ae60;
}

.correct-label {
  font-size: 0.8rem;
  color: var(--text-light);
  text-align: center;
  font-weight: 500;
}

.option-input {
  flex: 1;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 1rem;
  background: white;
  transition: border-color 0.2s ease;
}

.option-input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 2px rgba(66, 133, 244, 0.1);
}

.option-input::placeholder {
  color: #999;
  font-style: italic;
}

.remove-option-btn {
  background: #e74c3c;
  color: white;
  border: none;
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 500;
  transition: all 0.2s ease;
  min-width: 70px;
}

.remove-option-btn:hover {
  background: #c0392b;
  transform: translateY(-1px);
}

.add-option-btn {
  background: linear-gradient(135deg, var(--secondary-color) 0%, #27ae60 100%);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  cursor: pointer;
  margin-top: 1rem;
  font-size: 0.95rem;
  font-weight: 600;
  transition: all 0.3s ease;
  box-shadow: 0 2px 4px rgba(46, 204, 113, 0.2);
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

.add-option-btn:hover {
  background: linear-gradient(135deg, #27ae60 0%, #2ecc71 100%);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(46, 204, 113, 0.3);
}

/* Text answer options */
.text-answers-container {
  margin-top: 1rem;
}

.text-answer-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.5rem;
}

.text-answer-input {
  flex: 1;
  padding: 0.5rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
}

.remove-text-answer-btn {
  background: #95a5a6;
  color: white;
  border: none;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.8rem;
}

.remove-text-answer-btn:hover {
  background: #7f8c8d;
}

.add-text-answer-btn {
  background: var(--secondary-color);
  color: white;
  border: none;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  cursor: pointer;
  margin-top: 0.5rem;
  transition: background 0.2s;
}

.add-text-answer-btn:hover {
  background: #27ae60;
}

/* Explanation field */
.explanation-input {
  width: 100%;
  min-height: 60px;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  font-family: inherit;
  resize: vertical;
}

/* Quiz list styles */
.quizzes-list {
  margin-top: 1rem;
}

.quiz-item {
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1rem;
}

.quiz-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.quiz-info h4 {
  margin: 0 0 0.5rem 0;
  color: var(--primary-color);
}

.quiz-info p {
  margin: 0 0 0.5rem 0;
  color: var(--text-light);
}

.quiz-meta {
  font-size: 0.9rem;
  color: var(--text-light);
}

.quiz-actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.quiz-actions .btn-admin {
  padding: 0.5rem 1rem;
  font-size: 0.9rem;
}

/* Dark mode support */
[data-theme="dark"] .question-item {
  background: #2d3142;
  border-color: #4a5568;
}

[data-theme="dark"] .quiz-item {
  background: #2d3142;
  border-color: #4a5568;
}

[data-theme="dark"] .option-item {
  background: #2d3142;
  border-color: #4a5568;
}

[data-theme="dark"] .option-item:hover {
  border-color: #4285F4;
  box-shadow: 0 2px 8px rgba(66, 133, 244, 0.2);
}

[data-theme="dark"] .option-item.correct-selected {
  border-color: #27ae60;
  background: rgba(39, 174, 96, 0.1);
}

[data-theme="dark"] .options-header {
  background: rgba(66, 133, 244, 0.15);
  color: #4285F4;
  border-left-color: #4285F4;
}

[data-theme="dark"] .correct-label {
  color: #a0aec0;
}

[data-theme="dark"] .question-text-input,
[data-theme="dark"] .option-input,
[data-theme="dark"] .text-answer-input,
[data-theme="dark"] .explanation-input {
  background: #4a5568;
  border-color: #718096;
  color: #e2e8f0;
}

[data-theme="dark"] .option-input {
  background: #374151;
}

[data-theme="dark"] .option-input:focus {
  border-color: #4285F4;
  box-shadow: 0 0 0 2px rgba(66, 133, 244, 0.2);
}

[data-theme="dark"] .question-text-input::placeholder,
[data-theme="dark"] .option-input::placeholder,
[data-theme="dark"] .text-answer-input::placeholder,
[data-theme="dark"] .explanation-input::placeholder {
  color: #a0aec0;
}

/* Mobile responsiveness */
@media (max-width: 768px) {
  .question-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
  
  .quiz-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
  
  .quiz-actions {
    width: 100%;
  }
  
  .quiz-actions .btn-admin {
    flex: 1;
    text-align: center;
  }
  
  .option-item,
  .text-answer-item {
    flex-direction: column;
    align-items: stretch;
    gap: 0.5rem;
  }
  
  .question-type-selector {
    flex-direction: column;
    gap: 0.5rem;
  }
}

/* Dark mode support for isomer buttons */
[data-theme="dark"] .btn-generate,
[data-theme="dark"] .btn-download-pdf {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

[data-theme="dark"] .btn-generate:hover,
[data-theme="dark"] .btn-download-pdf:hover {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
}

/* Dropdown menu styles */
.dropdown-trigger {
  position: relative;
  cursor: pointer;
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  min-width: 200px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s var(--ease-smooth);
  z-index: 1000;
  backdrop-filter: blur(10px);
}

.dropdown-trigger:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-item {
  display: block;
  padding: var(--spacing-sm) var(--spacing-md);
  color: var(--text-color);
  text-decoration: none;
  transition: all 0.3s var(--ease-smooth);
  border-bottom: 1px solid var(--border-color);
}

.dropdown-item:last-child {
  border-bottom: none;
}

.dropdown-item:hover {
  background: var(--primary-light);
  color: var(--primary-color);
}

.dropdown-item.active {
  background: var(--primary-color);
  color: #fff;
}

.dropdown-item.active:hover {
  background: var(--primary-dark);
}

/* Isomer dropdown styles - copied from user dropdown */
.isomer-dropdown-trigger {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.3rem;
  padding: 1rem 1.5rem;
  background: transparent;
  border: none;
  color: rgba(255, 255, 255, 0.9);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  border-radius: 16px;
  line-height: 1.2;
  overflow: hidden;
  backdrop-filter: blur(10px);
  min-height: 44px;
}

.isomer-dropdown-trigger::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s;
}

.isomer-dropdown-trigger:hover::before {
  left: 100%;
}

.isomer-dropdown-trigger::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #ffffff, #f0f8ff);
  transform: translateX(-50%);
  transition: width 0.4s ease;
}

.isomer-dropdown-trigger:hover {
  background: rgba(255, 255, 255, 0.15);
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.isomer-dropdown-trigger:hover::after {
  width: 80%;
}

.isomer-dropdown-trigger .dropdown-arrow {
  display: none;
}

.isomer-dropdown-trigger[aria-expanded="true"] .dropdown-arrow {
  display: none;
}

.isomer-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  min-width: 200px;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s ease;
  padding: var(--spacing-xs) 0;
}

.isomer-dropdown-menu.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.isomer-dropdown-menu .dropdown-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  color: var(--text-color);
  text-decoration: none;
  transition: background-color 0.2s ease;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
  font: inherit;
}

.isomer-dropdown-menu .dropdown-link:hover {
  background: var(--primary-color);
  color: white;
}

.isomer-dropdown-menu .dropdown-link.active {
  background: var(--primary-color);
  color: white;
}

/* Calcule dropdown styles */
.calcule-dropdown-trigger {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.3rem;
  padding: 1rem 1.5rem;
  background: transparent;
  border: none;
  color: rgba(255, 255, 255, 0.9);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  border-radius: 16px;
  line-height: 1.2;
  overflow: hidden;
  backdrop-filter: blur(10px);
  min-height: 44px;
}

.calcule-dropdown-trigger::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.6s;
}

.calcule-dropdown-trigger:hover::before {
  left: 100%;
}

.calcule-dropdown-trigger::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #ffffff, #f0f8ff);
  transform: translateX(-50%);
  transition: width 0.4s ease;
}

.calcule-dropdown-trigger:hover {
  background: rgba(255, 255, 255, 0.15);
  color: #ffffff;
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.calcule-dropdown-trigger:hover::after {
  width: 80%;
}

.calcule-dropdown-trigger .dropdown-arrow {
  display: none;
}

.calcule-dropdown-trigger[aria-expanded="true"] .dropdown-arrow {
  display: none;
}

.calcule-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: white;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--card-shadow);
  min-width: 200px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s ease;
  z-index: 1000;
}

.calcule-dropdown-menu.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.calcule-dropdown-menu .dropdown-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  color: var(--text-primary);
  text-decoration: none;
  transition: all 0.3s ease;
  border-bottom: 1px solid var(--border-color);
}

.calcule-dropdown-menu .dropdown-link:last-child {
  border-bottom: none;
}

.calcule-dropdown-menu .dropdown-link:hover {
  background: var(--hover-bg);
  color: var(--primary-color);
  transform: translateX(5px);
}

.calcule-dropdown-menu .dropdown-link.active {
  background: var(--primary-color);
  color: white;
}

/* Dark theme support for calcule dropdown */
[data-theme="dark"] .calcule-dropdown-menu {
  background: var(--card-bg);
}

[data-theme="dark"] .calcule-dropdown-menu .dropdown-link {
  color: var(--text-primary);
}

/* Structure page specific styles */
.structure-container {
  display: flex;
  justify-content: center;
  align-items: center;
  margin: var(--spacing-lg) 0;
  padding: var(--spacing-lg);
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  min-height: 400px;
  min-width: 400px;
}

.structure-container img {
  max-width: 100%;
  max-height: 400px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background: #fff;
}

.structure-info {
  margin-top: var(--spacing-md);
  padding: var(--spacing-md);
  background: var(--card-background);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  text-align: center;
}

.structure-info p {
  margin: 0;
  font-size: 1.1rem;
  color: var(--text-color);
}

/* Dark mode support for dropdown */
[data-theme="dark"] .dropdown-menu {
  background: var(--card-background);
  border-color: var(--border-color);
}

[data-theme="dark"] .dropdown-item:hover {
  background: rgba(102, 126, 234, 0.1);
  color: var(--primary-color);
}

[data-theme="dark"] .structure-container img {
  background: #fff;
  border-color: var(--border-color);
}