/* Pro Bonana - Neo Brutalism Design System */
/* Enhanced v3.0 - Polished with refined aesthetics */

/* ===== CSS Variables ===== */
:root {
  /* Colors - Warmer, more refined palette */
  --bg-primary: #FFFDF7;
  --bg-secondary: #FFF8ED;
  --bg-tertiary: #FFFBF0;
  --bg-card: #FFFFFF;
  --text-primary: #18181B;
  --text-secondary: #3F3F46;
  --text-muted: #71717A;
  --border-color: #18181B;

  /* Accent Colors - Refined vibrant palette */
  --accent-yellow: #FBBF24;
  --accent-yellow-light: #FDE68A;
  --accent-green: #34D399;
  --accent-green-light: #A7F3D0;
  --accent-pink: #F472B6;
  --accent-pink-light: #FBCFE8;
  --accent-purple: #A78BFA;
  --accent-purple-light: #DDD6FE;
  --accent-orange: #FB923C;
  --accent-cyan: #22D3EE;
  --accent-blue: #60A5FA;
  --accent-red: #F87171;

  /* Premium Gradients */
  --gradient-yellow: linear-gradient(135deg, #FBBF24 0%, #FDE047 50%, #FEF08A 100%);
  --gradient-green: linear-gradient(135deg, #34D399 0%, #6EE7B7 100%);
  --gradient-pink: linear-gradient(135deg, #F472B6 0%, #FB7185 100%);
  --gradient-purple: linear-gradient(135deg, #A78BFA 0%, #C4B5FD 100%);
  --gradient-hero: linear-gradient(135deg, #FBBF24 0%, #F59E0B 50%, #D97706 100%);
  --gradient-premium: linear-gradient(135deg, #667eea 0%, #764ba2 100%);

  /* Borders - Slightly softer */
  --border-thin: 2px solid var(--border-color);
  --border-thick: 3px solid var(--border-color);
  --border-extra: 4px solid var(--border-color);

  /* Shadows - Refined Neo Brutalism with subtle depth */
  --shadow-xs: 2px 2px 0 var(--border-color);
  --shadow-sm: 3px 3px 0 var(--border-color);
  --shadow-md: 5px 5px 0 var(--border-color);
  --shadow-lg: 7px 7px 0 var(--border-color);
  --shadow-xl: 10px 10px 0 var(--border-color);
  --shadow-soft: 0 4px 20px rgba(0, 0, 0, 0.08);
  --shadow-glow: 0 0 30px rgba(251, 191, 36, 0.3);

  /* Typography */
  --font-primary: 'Space Grotesk', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'Space Mono', ui-monospace, monospace;

  /* Spacing - More refined scale */
  --space-2xs: 0.25rem;
  --space-xs: 0.5rem;
  --space-sm: 0.875rem;
  --space-md: 1.25rem;
  --space-lg: 1.75rem;
  --space-xl: 2.5rem;
  --space-2xl: 3.5rem;
  --space-3xl: 5rem;

  /* Border Radius */
  --radius-xs: 2px;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 12px;

  /* Transitions - Smoother */
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-bounce: 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* Z-Index Scale */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-modal: 1000;
  --z-toast: 9000;
  --z-loader: 9999;
}

/* ===== Dark Mode Variables ===== */
[data-theme="dark"] {
  /* IMPORTANT: Keep borders BLACK for Neo Brutalism aesthetic */
  --border-color: #1A1A1A;

  /* Dark backgrounds */
  --bg-primary: #1E1E1E;
  --bg-secondary: #2A2A2A;
  --bg-tertiary: #333333;

  /* Bright text for legibility */
  --text-primary: #FFFFFF;
  --text-secondary: #D0D0D0;
  --text-muted: #A0A0A0;

  /* Accent colors stay vibrant */
  --accent-yellow: #FFD93D;
  --accent-green: #6BCB77;
  --accent-pink: #FF6B9D;
  --accent-purple: #A66CFF;
  --accent-orange: #FF9F45;
  --accent-cyan: #4ECDC4;
  --accent-blue: #5B8DEE;
  --accent-red: #FF6B6B;

  /* Shadows stay BLACK */
  --shadow-sm: 4px 4px 0 #1A1A1A;
  --shadow-md: 6px 6px 0 #1A1A1A;
  --shadow-lg: 8px 8px 0 #1A1A1A;
  --shadow-xl: 12px 12px 0 #1A1A1A;
}

/* Dark mode transitions */
body,
.header,
.card,
.btn,
.form-input,
.form-textarea,
.form-select,
.nav-links a,
.modal,
.modal-header,
.admin-sidebar,
.admin-table,
.footer,
.toast,
.filter-pill,
.search-input,
.resource-item,
.tag,
.badge,
.stats-bar,
.login-card {
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* ===== Dark Mode Component Overrides ===== */

/* Header */
[data-theme="dark"] .header {
  background: var(--accent-yellow);
}

[data-theme="dark"] .logo-icon {
  background: #1A1A1A;
  color: var(--accent-yellow);
}

[data-theme="dark"] .nav-links a {
  background: var(--bg-primary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .nav-links a:hover {
  background: #1A1A1A;
  color: var(--bg-primary);
}

/* Hero Section */
[data-theme="dark"] .hero {
  background: linear-gradient(135deg, #2A2A2A 0%, #1E1E1E 100%);
  border-bottom-color: #1A1A1A;
}

[data-theme="dark"] .hero h1,
[data-theme="dark"] .hero p {
  color: var(--text-primary);
}

/* Cards */
[data-theme="dark"] .card {
  background: var(--bg-secondary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .card-header {
  border-bottom-color: #1A1A1A;
}

[data-theme="dark"] .card-title {
  color: var(--text-primary);
}

[data-theme="dark"] .card-description {
  color: var(--text-secondary);
}

/* Buttons */
[data-theme="dark"] .btn {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .btn-primary {
  background: var(--accent-yellow);
  color: #1A1A1A;
}

[data-theme="dark"] .btn-secondary {
  background: #1A1A1A;
  color: var(--text-primary);
}

[data-theme="dark"] .btn-danger {
  background: var(--accent-pink);
  color: #1A1A1A;
}

[data-theme="dark"] .btn-success {
  background: var(--accent-blue);
  color: #1A1A1A;
}

/* Footer */
[data-theme="dark"] .footer {
  background: var(--bg-secondary);
  border-top-color: #1A1A1A;
}

/* Stats Bar */
[data-theme="dark"] .stats-bar {
  background: var(--bg-secondary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .stat-value {
  color: var(--text-primary);
}

[data-theme="dark"] .stat-label {
  color: var(--text-secondary);
}

/* Filter Pills */
[data-theme="dark"] .filter-pill {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .filter-pill.active {
  background: var(--accent-yellow);
  color: #1A1A1A;
}

[data-theme="dark"] .filter-label {
  color: var(--text-primary);
}

/* Search Input */
[data-theme="dark"] .search-input {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .search-input::placeholder {
  color: var(--text-muted);
}

/* Tags */
[data-theme="dark"] .tag {
  background: var(--bg-tertiary);
  border-color: #1A1A1A;
  color: var(--text-primary);
}

/* Resource Items */
[data-theme="dark"] .resource-item {
  background: var(--bg-secondary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .resource-title {
  color: var(--text-primary);
}

[data-theme="dark"] .resource-link {
  background: var(--accent-yellow);
  color: #1A1A1A;
  border-color: #1A1A1A;
}

/* Modals */
[data-theme="dark"] .modal {
  background: var(--bg-secondary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .modal-header {
  background: var(--accent-yellow);
  border-bottom-color: #1A1A1A;
  color: #1A1A1A;
}

[data-theme="dark"] .modal-title {
  color: #1A1A1A;
}

[data-theme="dark"] .modal-close {
  background: var(--bg-primary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .modal-body {
  color: var(--text-primary);
}

[data-theme="dark"] .modal-footer {
  border-top-color: #1A1A1A;
}

/* Admin Sidebar */
[data-theme="dark"] .admin-sidebar {
  background: var(--bg-secondary);
  border-right-color: #1A1A1A;
}

[data-theme="dark"] .admin-sidebar h3 {
  color: var(--text-primary);
}

[data-theme="dark"] .sidebar-nav a {
  color: var(--text-primary);
}

[data-theme="dark"] .sidebar-nav a:hover,
[data-theme="dark"] .sidebar-nav a.active {
  background: var(--bg-tertiary);
  border-color: #1A1A1A;
}

/* Admin Tables */
[data-theme="dark"] .admin-table {
  border-color: #1A1A1A;
}

[data-theme="dark"] .admin-table th {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .admin-table td {
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .admin-table tr:hover td {
  background: var(--bg-tertiary);
}

/* Form Elements */
[data-theme="dark"] .form-input,
[data-theme="dark"] .form-textarea,
[data-theme="dark"] .form-select {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .form-input::placeholder,
[data-theme="dark"] .form-textarea::placeholder {
  color: var(--text-muted);
}

[data-theme="dark"] .form-label {
  color: var(--text-primary);
}

/* Login Card */
[data-theme="dark"] .login-card {
  background: var(--bg-secondary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .login-header h2,
[data-theme="dark"] .login-header p {
  color: var(--text-primary);
}

[data-theme="dark"] .login-icon {
  border-color: #1A1A1A;
}

/* Loader */
[data-theme="dark"] .loader-overlay {
  background: var(--bg-primary);
}

[data-theme="dark"] .loader-logo {
  background: var(--accent-yellow);
  color: #1A1A1A;
  border-color: #1A1A1A;
}

[data-theme="dark"] .loader-text {
  color: var(--text-primary);
}

[data-theme="dark"] .loader-dots span {
  background: var(--text-primary);
}

/* Empty State */
[data-theme="dark"] .empty-state {
  border-color: #1A1A1A;
  color: var(--text-primary);
}

[data-theme="dark"] .empty-state h3 {
  color: var(--text-primary);
}

[data-theme="dark"] .empty-state p {
  color: var(--text-secondary);
}

/* Video Cards */
[data-theme="dark"] .video-card {
  background: var(--bg-secondary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .video-title {
  color: var(--text-primary);
}

[data-theme="dark"] .video-embed {
  border-bottom-color: #1A1A1A;
}

/* Course Header */
[data-theme="dark"] .course-header {
  background: var(--bg-secondary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .course-header h1 {
  color: var(--text-primary);
}

/* Section Title */
[data-theme="dark"] .section-title {
  color: var(--text-primary);
  border-bottom-color: #1A1A1A;
}

/* Back Link */
[data-theme="dark"] .back-link {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border-color: #1A1A1A;
}

[data-theme="dark"] .back-link:hover {
  background: var(--accent-yellow);
  color: #1A1A1A;
}

/* Badges */
[data-theme="dark"] .badge-semester {
  border-color: #1A1A1A;
}

[data-theme="dark"] .badge-subject {
  border-color: #1A1A1A;
}

/* Page Title */
[data-theme="dark"] .page-title {
  border-bottom-color: #1A1A1A;
}

[data-theme="dark"] .page-title h1 {
  color: var(--text-primary);
}

/* Scrollbar */
[data-theme="dark"] ::-webkit-scrollbar-track {
  background: var(--bg-secondary);
  border-left-color: #1A1A1A;
}

[data-theme="dark"] ::-webkit-scrollbar-thumb {
  background: var(--accent-yellow);
  border-color: #1A1A1A;
}

/* Selection */
[data-theme="dark"] ::selection {
  background: var(--accent-yellow);
  color: #1A1A1A;
}

/* Error Message */
[data-theme="dark"] .error-message {
  border-color: #1A1A1A;
}

/* ===== Dark Mode Toggle (Header) ===== */
.theme-toggle {
  width: 40px;
  height: 40px;
  border: var(--border-thick);
  border-radius: 50%;
  background: var(--bg-primary);
  color: #1A1A1A;
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
}

.theme-toggle:hover {
  transform: scale(1.1) rotate(15deg);
  background: var(--accent-yellow);
  box-shadow: var(--shadow-sm);
}

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

[data-theme="dark"] .theme-toggle {
  background: var(--bg-tertiary);
  color: var(--accent-yellow);
  border-color: #1A1A1A;
}

[data-theme="dark"] .theme-toggle:hover {
  background: var(--accent-yellow);
  color: #1A1A1A;
}

/* ===== Apply Admin Link (Subtle) ===== */
.apply-admin-link {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
  text-decoration: none;
  padding: var(--space-xs) var(--space-sm);
  border: 2px dashed var(--text-muted);
  background: transparent;
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  transition: all 0.2s ease;
  opacity: 0.7;
}

.apply-admin-link:hover {
  opacity: 1;
  color: var(--text-secondary);
  border-color: var(--text-secondary);
  border-style: solid;
  transform: translateY(-2px);
}

[data-theme="dark"] .apply-admin-link {
  color: var(--text-muted);
  border-color: var(--text-muted);
}

[data-theme="dark"] .apply-admin-link:hover {
  color: var(--text-secondary);
  border-color: var(--text-secondary);
}

/* ===== Keyframe Animations ===== */
@keyframes pulse {

  0%,
  100% {
    transform: scale(1);
  }

  50% {
    transform: scale(1.05);
  }
}

@keyframes bounce {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-10px);
  }
}

@keyframes shake {

  0%,
  100% {
    transform: translateX(0);
  }

  25% {
    transform: translateX(-5px);
  }

  75% {
    transform: translateX(5px);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }

  to {
    opacity: 1;
    transform: translateX(0);
  }
}

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

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

@keyframes loaderPulse {

  0%,
  100% {
    transform: scale(1);
    box-shadow: 0 0 0 0 rgba(255, 217, 61, 0.7);
  }

  50% {
    transform: scale(1.1);
    box-shadow: 0 0 0 20px rgba(255, 217, 61, 0);
  }
}

@keyframes textReveal {
  0% {
    opacity: 0;
    letter-spacing: 0.5em;
  }

  100% {
    opacity: 1;
    letter-spacing: -0.02em;
  }
}

@keyframes cardFloat {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-5px);
  }
}

@keyframes shimmer {
  0% {
    background-position: -200% 0;
  }

  100% {
    background-position: 200% 0;
  }
}

/* ===== Reset & Base ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

/* ===== Typography ===== */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-mono);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 3rem;
}

h2 {
  font-size: 2.25rem;
}

h3 {
  font-size: 1.75rem;
}

h4 {
  font-size: 1.25rem;
}

p {
  font-size: 1rem;
  color: var(--text-secondary);
}

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

/* ===== Layout ===== */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ===== Header ===== */
.header {
  background: var(--accent-yellow);
  border-bottom: var(--border-extra);
  padding: var(--space-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-family: var(--font-mono);
  font-size: 1.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: var(--text-primary);
  border: var(--border-thick);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-yellow);
  font-weight: 900;
}

.nav-links {
  display: flex;
  gap: var(--space-md);
  list-style: none;
}

.nav-links a {
  font-family: var(--font-mono);
  font-weight: 600;
  padding: var(--space-xs) var(--space-sm);
  border: var(--border-thick);
  background: var(--bg-primary);
  transition: all 0.15s ease;
}

.nav-links a:hover {
  background: var(--text-primary);
  color: var(--bg-primary);
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-sm);
}

/* ===== Main Content ===== */
.main {
  padding: var(--space-xl) 0;
}

.page-title {
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  border-bottom: var(--border-thick);
}

/* ===== Cards ===== */
.card {
  background: var(--bg-card);
  border: var(--border-thick);
  box-shadow: var(--shadow-sm);
  padding: var(--space-lg);
  transition: all var(--transition-smooth);
  position: relative;
}

.card:hover {
  transform: translate(-3px, -3px);
  box-shadow: var(--shadow-md);
}

.card-header {
  height: 6px;
  margin: calc(-1 * var(--space-lg));
  margin-bottom: var(--space-md);
  border-bottom: var(--border-thin);
  border-radius: var(--radius-xs) var(--radius-xs) 0 0;
}

.card-title {
  font-size: clamp(1.25rem, 3vw, 1.5rem);
  margin-bottom: var(--space-xs);
  line-height: 1.3;
}

.card-description {
  font-size: 0.9rem;
  margin-bottom: var(--space-md);
  line-height: 1.5;
  color: var(--text-secondary);
}

/* ===== Course Grid ===== */
.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-lg);
}

.course-card {
  cursor: pointer;
}

.course-card .card-meta {
  display: flex;
  gap: var(--space-sm);
  margin-top: var(--space-md);
  flex-wrap: wrap;
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 10px;
  background: var(--bg-secondary);
  border: var(--border-thin);
}

/* ===== Buttons ===== */
.btn {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 600;
  padding: 0.75rem 1.25rem;
  border: var(--border-thin);
  background: var(--bg-card);
  cursor: pointer;
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  text-decoration: none;
  white-space: nowrap;
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-xs);
}

.btn:active {
  transform: translate(0, 0);
  box-shadow: none;
}

.btn-primary {
  background: var(--accent-yellow);
  border-color: var(--border-color);
  color: var(--text-primary);
}

.btn-primary:hover {
  background: var(--accent-yellow-light);
  box-shadow: var(--shadow-sm), var(--shadow-glow);
}

.btn-secondary {
  background: var(--text-primary);
  color: var(--bg-primary);
  border-color: var(--text-primary);
}

.btn-secondary:hover {
  background: var(--text-secondary);
}

.btn-danger {
  background: var(--accent-pink);
  color: var(--text-primary);
}

.btn-danger:hover {
  background: var(--accent-pink-light);
}

.btn-success {
  background: var(--accent-green);
  color: var(--text-primary);
}

.btn-success:hover {
  background: var(--accent-green-light);
}

.btn-outline {
  background: transparent;
  border: var(--border-thin);
}

.btn-outline:hover {
  background: var(--bg-secondary);
}

/* ===== Forms ===== */
.form-group {
  margin-bottom: var(--space-md);
}

.form-label {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  margin-bottom: var(--space-xs);
  font-size: 0.9rem;
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  font-family: var(--font-primary);
  font-size: 1rem;
  padding: var(--space-sm);
  border: var(--border-thick);
  background: var(--bg-primary);
  transition: all 0.15s ease;
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  box-shadow: var(--shadow-sm);
  transform: translate(-2px, -2px);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

/* ===== Course Detail Page ===== */
.course-header {
  padding: var(--space-lg);
  border: var(--border-extra);
  box-shadow: var(--shadow-lg);
  margin-bottom: var(--space-xl);
}

.course-header h1 {
  margin-bottom: var(--space-xs);
}

.section {
  margin-bottom: var(--space-xl);
}

.section-title {
  font-size: 1.5rem;
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-xs);
  border-bottom: var(--border-thick);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.section-icon {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: var(--border-thick);
  font-size: 1.2rem;
}

/* ===== Video Grid ===== */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: var(--space-lg);
}

.video-card {
  border: var(--border-extra);
  background: var(--bg-primary);
  overflow: hidden;
}

.video-embed {
  width: 100%;
  aspect-ratio: 16/9;
  border-bottom: var(--border-thick);
}

.video-embed iframe {
  width: 100%;
  height: 100%;
  border: none;
}

.video-title {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 600;
  padding: var(--space-sm);
}

/* ===== Resource List ===== */
.resource-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.resource-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-sm) var(--space-md);
  border: var(--border-thick);
  background: var(--bg-primary);
  transition: all 0.15s ease;
}

.resource-item:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-sm);
}

.resource-info {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.resource-icon {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-orange);
  border: var(--border-thin);
  font-size: 1rem;
}

.resource-title {
  font-family: var(--font-mono);
  font-weight: 600;
}

.resource-link {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  padding: 6px 12px;
  background: var(--text-primary);
  color: var(--bg-primary);
  border: var(--border-thin);
  transition: all 0.15s ease;
}

.resource-link:hover {
  background: var(--accent-yellow);
  color: var(--text-primary);
}

/* ===== Admin Login ===== */
.login-container {
  display: flex;
  min-height: calc(100vh - 80px);
  align-items: center;
  justify-content: center;
  padding: var(--space-lg);
}

.login-card {
  width: 100%;
  max-width: 420px;
  padding: var(--space-lg);
  background: var(--bg-primary);
  border: var(--border-extra);
  box-shadow: var(--shadow-lg);
}

.login-header {
  text-align: center;
  margin-bottom: var(--space-lg);
}

.login-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto var(--space-md);
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-purple);
  border: var(--border-extra);
  font-size: 2rem;
}

.error-message {
  background: var(--accent-pink);
  border: var(--border-thick);
  padding: var(--space-sm);
  margin-bottom: var(--space-md);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  display: none;
}

.error-message.show {
  display: block;
}

/* ===== Admin Dashboard ===== */
.admin-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  min-height: calc(100vh - 80px);
}

.admin-sidebar {
  background: var(--bg-secondary);
  border-right: var(--border-extra);
  padding: var(--space-lg);
}

.sidebar-nav {
  list-style: none;
}

.sidebar-nav li {
  margin-bottom: var(--space-xs);
}

.sidebar-nav a {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm);
  font-family: var(--font-mono);
  font-weight: 600;
  border: 2px solid transparent;
  transition: all 0.15s ease;
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
  background: var(--bg-primary);
  border: var(--border-thin);
}

.admin-content {
  padding: var(--space-lg);
}

.admin-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-md);
  border-bottom: var(--border-thick);
}

/* ===== Admin Tables ===== */
.admin-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  border: var(--border-thick);
}

.admin-table th,
.admin-table td {
  padding: var(--space-sm);
  text-align: left;
  border-bottom: var(--border-thin);
}

.admin-table th {
  font-family: var(--font-mono);
  background: var(--bg-secondary);
  font-weight: 700;
}

.admin-table tr:last-child td {
  border-bottom: none;
}

.admin-table tr:hover td {
  background: var(--bg-secondary);
}

.table-actions {
  display: flex;
  gap: var(--space-xs);
}

.table-actions .btn {
  padding: 6px 12px;
  font-size: 0.85rem;
}

/* ===== Modal ===== */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.2s ease;
}

.modal-overlay.show {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: var(--bg-primary);
  border: var(--border-extra);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 600px;
  max-height: 90vh;
  overflow-y: auto;
  transform: translateY(20px);
  transition: transform 0.2s ease;
}

.modal-overlay.show .modal {
  transform: translateY(0);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-md);
  border-bottom: var(--border-thick);
  background: var(--accent-yellow);
}

.modal-title {
  font-size: 1.25rem;
}

.modal-close {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-primary);
  border: var(--border-thick);
  font-size: 1.5rem;
  cursor: pointer;
  transition: all 0.15s ease;
}

.modal-close:hover {
  background: var(--text-primary);
  color: var(--bg-primary);
}

.modal-body {
  padding: var(--space-lg);
}

.modal-footer {
  padding: var(--space-md);
  border-top: var(--border-thick);
  display: flex;
  justify-content: flex-end;
  gap: var(--space-sm);
}

/* ===== Empty State ===== */
.empty-state {
  text-align: center;
  padding: var(--space-xl);
  border: var(--border-thick);
  border-style: dashed;
}

.empty-state-icon {
  font-size: 3rem;
  margin-bottom: var(--space-md);
}

.empty-state h3 {
  margin-bottom: var(--space-xs);
}

.empty-state p {
  margin-bottom: var(--space-md);
}

/* ===== Back Button ===== */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-family: var(--font-mono);
  font-weight: 600;
  margin-bottom: var(--space-lg);
  padding: var(--space-xs) var(--space-sm);
  border: var(--border-thick);
  background: var(--bg-primary);
  transition: all 0.15s ease;
}

.back-link:hover {
  background: var(--accent-yellow);
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-sm);
}

/* ===== Color Picker ===== */
.color-options {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.color-option {
  width: 40px;
  height: 40px;
  border: var(--border-thick);
  cursor: pointer;
  transition: all 0.15s ease;
}

.color-option:hover,
.color-option.selected {
  transform: scale(1.1);
  box-shadow: var(--shadow-sm);
}

/* ===== Utility Classes ===== */
.text-center {
  text-align: center;
}

.mt-sm {
  margin-top: var(--space-sm);
}

.mt-md {
  margin-top: var(--space-md);
}

.mt-lg {
  margin-top: var(--space-lg);
}

.mb-sm {
  margin-bottom: var(--space-sm);
}

.mb-md {
  margin-bottom: var(--space-md);
}

.mb-lg {
  margin-bottom: var(--space-lg);
}

/* ===== Mobile Navigation Toggle ===== */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 44px;
  height: 44px;
  background: var(--bg-primary);
  border: var(--border-thick);
  cursor: pointer;
  gap: 5px;
  transition: all 0.2s ease;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 3px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.nav-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
  transform: translateX(-10px);
}

.nav-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(6px, -6px);
}

.nav-toggle:hover {
  background: var(--accent-yellow);
  box-shadow: var(--shadow-sm);
  transform: translate(-2px, -2px);
}

/* ===== Responsive ===== */

/* Extra Small Devices (phones in portrait) */
@media (max-width: 480px) {
  html {
    font-size: 14px;
  }

  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  h3 {
    font-size: 1.25rem;
  }

  .container {
    padding: 0 var(--space-sm);
  }

  .hero {
    padding: var(--space-lg) 0;
    margin-bottom: var(--space-md);
  }

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

  .hero p {
    font-size: 1rem;
    padding: 0 var(--space-sm);
  }

  .stats-bar {
    flex-wrap: wrap;
    gap: var(--space-sm);
    padding: var(--space-sm);
  }

  .stat-item {
    flex: 1 1 calc(50% - var(--space-sm));
    min-width: 80px;
    padding: var(--space-xs);
  }

  .stat-value {
    font-size: 1.5rem;
  }

  .stat-label {
    font-size: 0.7rem;
  }

  .card {
    padding: var(--space-sm);
  }

  .card-title {
    font-size: 1.2rem;
  }

  .card-description {
    font-size: 0.9rem;
  }

  .btn {
    padding: var(--space-sm);
    font-size: 0.9rem;
    min-height: 44px;
    width: 100%;
    justify-content: center;
  }

  .modal {
    margin: var(--space-sm);
    max-height: calc(100vh - var(--space-lg));
  }

  .modal-body {
    padding: var(--space-md);
  }

  .resource-item {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-sm);
    padding: var(--space-sm);
  }

  .resource-link {
    width: 100%;
    text-align: center;
    padding: var(--space-sm);
    min-height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .footer-content {
    flex-direction: column;
    text-align: center;
  }

  .footer-left {
    align-items: center;
  }

  .footer-links {
    flex-direction: column;
    gap: var(--space-sm);
  }

  /* Touch-friendly table actions */
  .table-actions {
    flex-direction: column;
    gap: var(--space-xs);
  }

  .table-actions .btn {
    width: 100%;
    min-height: 40px;
  }
}

/* Small Devices (phones in landscape, small tablets) */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.75rem;
  }

  /* Header with hamburger menu */
  .header {
    padding: var(--space-sm) 0;
  }

  .header-content {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    position: relative;
  }

  .logo {
    font-size: 1.25rem;
  }

  .logo-icon {
    width: 36px;
    height: 36px;
    font-size: 0.9rem;
  }

  .nav-toggle {
    display: flex;
  }

  nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--accent-yellow);
    border-bottom: var(--border-extra);
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
    z-index: 99;
  }

  nav.active {
    max-height: 400px;
    padding: var(--space-md) 0;
  }

  .nav-links {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-xs);
    padding: 0 var(--space-md);
  }

  .nav-links a {
    width: 100%;
    text-align: center;
    padding: var(--space-sm);
    min-height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  /* Hero adjustments */
  .hero {
    padding: var(--space-xl) 0;
  }

  .hero h1 {
    font-size: 2.25rem;
  }

  /* Stats bar - horizontal scroll on mobile */
  .stats-bar {
    display: flex;
    gap: var(--space-md);
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scroll-snap-type: x mandatory;
    padding-bottom: var(--space-sm);
    margin-bottom: var(--space-md);
  }

  .stats-bar::-webkit-scrollbar {
    height: 6px;
  }

  .stat-item {
    flex-shrink: 0;
    scroll-snap-align: start;
    min-width: 100px;
  }

  /* Filter bar - horizontal scroll */
  .filter-bar {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-sm);
  }

  .filter-group {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-xs);
  }

  .filter-pills {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scroll-snap-type: x mandatory;
    padding-bottom: var(--space-xs);
    flex-wrap: nowrap;
  }

  .filter-pills::-webkit-scrollbar {
    height: 4px;
  }

  .filter-pill {
    flex-shrink: 0;
    scroll-snap-align: start;
    min-height: 44px;
    padding: var(--space-xs) var(--space-md);
  }

  .search-box {
    max-width: 100%;
    min-width: 100%;
  }

  .search-input {
    min-height: 48px;
  }

  /* Grid layouts */
  .admin-layout {
    grid-template-columns: 1fr;
  }

  .admin-sidebar {
    border-right: none;
    border-bottom: var(--border-extra);
    padding: var(--space-md);
  }

  .sidebar-nav {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
  }

  .sidebar-nav li {
    margin-bottom: 0;
  }

  .sidebar-nav a {
    padding: var(--space-xs) var(--space-sm);
    font-size: 0.85rem;
    min-height: 40px;
  }

  .video-grid {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  .course-grid {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  /* Course detail page */
  .course-header {
    padding: var(--space-md);
    margin-bottom: var(--space-lg);
  }

  .course-header h1 {
    font-size: 1.5rem;
  }

  .section-title {
    font-size: 1.25rem;
    flex-wrap: wrap;
  }

  .section-icon {
    width: 32px;
    height: 32px;
    font-size: 1rem;
  }

  /* Modal improvements */
  .modal-overlay {
    padding: var(--space-sm);
    align-items: flex-end;
  }

  .modal {
    max-width: 100%;
    border-radius: 12px 12px 0 0;
    max-height: 85vh;
  }

  .modal-footer {
    flex-direction: column;
    gap: var(--space-xs);
  }

  .modal-footer .btn {
    width: 100%;
  }

  /* Toast positioning */
  .toast {
    left: var(--space-sm);
    right: var(--space-sm);
    bottom: var(--space-md);
    width: auto;
  }

  /* Admin content */
  .admin-content {
    padding: var(--space-md);
  }

  .admin-header {
    flex-direction: column;
    gap: var(--space-md);
    align-items: stretch;
  }

  .admin-header h2 {
    font-size: 1.5rem;
  }

  /* Table responsive */
  .admin-table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .admin-table th,
  .admin-table td {
    min-width: 120px;
    font-size: 0.85rem;
  }

  /* Login improvements */
  .login-container {
    padding: var(--space-md);
    min-height: calc(100vh - 120px);
  }

  .login-card {
    padding: var(--space-md);
  }

  .login-icon {
    width: 60px;
    height: 60px;
    font-size: 1.5rem;
  }

  /* Back link */
  .back-link {
    font-size: 0.9rem;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
  }

  /* Empty state */
  .empty-state {
    padding: var(--space-lg);
  }

  .empty-state-icon {
    font-size: 2.5rem;
  }
}

/* Medium Devices (tablets) */
@media (min-width: 769px) and (max-width: 1024px) {
  .course-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .video-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .admin-layout {
    grid-template-columns: 220px 1fr;
  }

  .admin-sidebar {
    padding: var(--space-md);
  }

  .sidebar-nav a {
    font-size: 0.85rem;
    padding: var(--space-xs) var(--space-sm);
  }
}

/* Hover states only for devices that support hover */
@media (hover: hover) and (pointer: fine) {
  .card:hover {
    transform: translate(-4px, -4px);
    box-shadow: var(--shadow-lg);
  }

  .btn:hover {
    transform: translate(-2px, -2px);
    box-shadow: var(--shadow-sm);
  }

  .nav-links a:hover {
    background: var(--text-primary);
    color: var(--bg-primary);
    transform: translate(-2px, -2px);
    box-shadow: var(--shadow-sm);
  }
}

/* Touch devices - remove hover effects that could stick */
@media (hover: none) {
  .card:hover {
    transform: none;
    box-shadow: var(--shadow-md);
  }

  .btn:hover {
    transform: none;
  }

  .card:active {
    transform: scale(0.98);
  }

  .btn:active {
    transform: scale(0.95);
    opacity: 0.9;
  }

  .filter-pill:active {
    transform: scale(0.95);
  }
}

/* Landscape orientation on phones */
@media (max-height: 500px) and (orientation: landscape) {
  .hero {
    padding: var(--space-md) 0;
    margin-bottom: var(--space-md);
  }

  .hero h1 {
    font-size: 1.75rem;
  }

  .modal-overlay {
    align-items: center;
  }

  .modal {
    max-height: 90vh;
    border-radius: 0;
  }
}

/* Safe area insets for notched devices */
@supports (padding: max(0px)) {
  .header {
    padding-left: max(var(--space-md), env(safe-area-inset-left));
    padding-right: max(var(--space-md), env(safe-area-inset-right));
  }

  .footer {
    padding-bottom: max(var(--space-xl), env(safe-area-inset-bottom));
  }

  .modal {
    padding-bottom: max(var(--space-md), env(safe-area-inset-bottom));
  }

  .toast {
    bottom: max(var(--space-lg), calc(env(safe-area-inset-bottom) + var(--space-sm)));
  }
}

/* Reduced motion preference */
@media (prefers-reduced-motion: reduce) {

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }
}

/* ===== Custom PB Loader ===== */
.loader-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--bg-primary);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loader-overlay.hidden {
  opacity: 0;
  visibility: hidden;
}

.loader-logo {
  width: 100px;
  height: 100px;
  background: var(--accent-yellow);
  border: var(--border-extra);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--text-primary);
  animation: loaderPulse 1.5s ease-in-out infinite;
  box-shadow: var(--shadow-lg);
}

.loader-text {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 700;
  margin-top: var(--space-lg);
  animation: textReveal 1s ease forwards;
}

.loader-dots {
  display: flex;
  gap: var(--space-xs);
  margin-top: var(--space-sm);
}

.loader-dots span {
  width: 8px;
  height: 8px;
  background: var(--text-primary);
  border-radius: 50%;
  animation: bounce 0.6s ease-in-out infinite;
}

.loader-dots span:nth-child(2) {
  animation-delay: 0.1s;
}

.loader-dots span:nth-child(3) {
  animation-delay: 0.2s;
}

/* ===== Enhanced Cards with Animation ===== */
.card {
  animation: fadeIn 0.4s ease forwards;
  opacity: 0;
}

.card:nth-child(1) {
  animation-delay: 0.05s;
}

.card:nth-child(2) {
  animation-delay: 0.1s;
}

.card:nth-child(3) {
  animation-delay: 0.15s;
}

.card:nth-child(4) {
  animation-delay: 0.2s;
}

.card:nth-child(5) {
  animation-delay: 0.25s;
}

.card:nth-child(6) {
  animation-delay: 0.3s;
}

.course-card {
  position: relative;
  overflow: hidden;
}

.course-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg,
      transparent,
      rgba(255, 255, 255, 0.4),
      transparent);
  transition: left 0.5s ease;
}

.course-card:hover::before {
  left: 100%;
}

/* ===== Filter Bar ===== */
.filter-bar {
  display: flex;
  gap: var(--space-lg);
  margin-bottom: var(--space-xl);
  flex-wrap: wrap;
  align-items: flex-start;
  padding: var(--space-md);
  background: var(--bg-card);
  border: var(--border-thin);
  border-radius: var(--radius-sm);
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.filter-label {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.filter-pills {
  display: flex;
  gap: var(--space-2xs);
  flex-wrap: wrap;
}

.filter-pill {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  padding: 0.4rem 0.75rem;
  background: var(--bg-secondary);
  border: var(--border-thin);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-pill:hover {
  background: var(--bg-tertiary);
  transform: translateY(-1px);
}

.filter-pill.active {
  background: var(--accent-yellow);
  border-color: var(--border-color);
  font-weight: 600;
}

/* ===== Search Box ===== */
.search-box {
  position: relative;
  flex: 1;
  min-width: 200px;
  max-width: 350px;
}

.search-input {
  width: 100%;
  padding: 0.6rem 1rem;
  padding-left: 2.5rem;
  font-family: var(--font-primary);
  font-size: 0.9rem;
  border: var(--border-thin);
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  transition: all var(--transition-fast);
}

.search-input:focus {
  outline: none;
  background: var(--bg-card);
  border-color: var(--accent-yellow);
  box-shadow: 0 0 0 3px rgba(251, 191, 36, 0.2);
}

.search-input::placeholder {
  color: var(--text-muted);
}

.search-icon {
  position: absolute;
  left: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1rem;
  color: var(--text-muted);
}

/* ===== Course Badge/Chips ===== */
.badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  padding: 3px 8px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-semester {
  background: var(--accent-purple);
  color: white;
  border: 2px solid var(--text-primary);
}

.badge-subject {
  background: var(--accent-cyan);
  color: var(--text-primary);
  border: 2px solid var(--text-primary);
}

/* ===== Stats Bar ===== */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
  padding: var(--space-lg);
  background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-secondary) 100%);
  border: var(--border-thick);
  box-shadow: var(--shadow-sm);
  margin-bottom: var(--space-xl);
  position: relative;
}

.stats-bar::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-yellow), var(--accent-green), var(--accent-cyan), var(--accent-purple));
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2xs);
  padding: var(--space-sm);
  text-align: center;
  transition: transform var(--transition-fast);
}

.stat-item:hover {
  transform: translateY(-2px);
}

.stat-value {
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1;
}

.stat-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 500;
}

@media (max-width: 600px) {
  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-sm);
    padding: var(--space-md);
  }

  .stat-item {
    padding: var(--space-xs);
  }
}

/* ===== Hero Section ===== */
.hero {
  padding: var(--space-3xl) 0 var(--space-2xl);
  text-align: center;
  background: var(--gradient-hero);
  border-bottom: var(--border-extra);
  margin-bottom: var(--space-xl);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background:
    radial-gradient(circle at 20% 80%, rgba(255, 255, 255, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 40%);
  pointer-events: none;
}

.hero h1 {
  font-size: clamp(2.5rem, 8vw, 4rem);
  margin-bottom: var(--space-md);
  animation: textReveal 0.8s ease forwards;
  text-shadow: 2px 2px 0 rgba(0, 0, 0, 0.1);
  position: relative;
}

.hero-subtitle {
  font-size: clamp(1.25rem, 3vw, 1.5rem);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-sm);
  opacity: 0.9;
}

.hero-description {
  font-size: clamp(0.95rem, 2vw, 1.1rem);
  max-width: 550px;
  margin: 0 auto;
  color: var(--text-secondary);
  line-height: 1.6;
}

.hero p {
  max-width: 600px;
  margin: 0 auto;
  color: var(--text-primary);
}

/* ===== Toast Notifications ===== */
.toast {
  position: fixed;
  bottom: var(--space-lg);
  right: var(--space-lg);
  padding: var(--space-sm) var(--space-md);
  background: var(--text-primary);
  color: var(--bg-primary);
  border: var(--border-thick);
  box-shadow: var(--shadow-md);
  font-family: var(--font-mono);
  font-weight: 600;
  transform: translateY(100px);
  opacity: 0;
  transition: all 0.3s ease;
  z-index: 9000;
}

.toast.show {
  transform: translateY(0);
  opacity: 1;
}

.toast.success {
  background: var(--accent-green);
  color: var(--text-primary);
}

.toast.error {
  background: var(--accent-red);
  color: white;
}

/* ===== Skeleton Loading ===== */
.skeleton {
  background: linear-gradient(90deg,
      var(--bg-secondary) 25%,
      var(--bg-tertiary) 50%,
      var(--bg-secondary) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border: var(--border-thick);
}

.skeleton-card {
  height: 200px;
  margin-bottom: var(--space-md);
}

.skeleton-text {
  height: 20px;
  margin-bottom: var(--space-xs);
  width: 80%;
}

.skeleton-text.short {
  width: 50%;
}

/* ===== Improved Footer ===== */
.footer {
  border-top: var(--border-extra);
  padding: var(--space-xl) 0;
  background: var(--bg-secondary);
  margin-top: var(--space-2xl);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.25rem;
}

.footer-left {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer-links {
  display: flex;
  gap: var(--space-md);
  list-style: none;
}

.footer-links a {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  transition: all var(--transition-fast);
}

.footer-links a:hover {
  color: var(--accent-purple);
}

/* ===== Print Styles ===== */
@media print {

  .header,
  .footer,
  .btn,
  .filter-bar {
    display: none;
  }

  .card {
    box-shadow: none;
    border: 1px solid #000;
  }
}

/* ===== Enhanced UX 2025 ===== */

/* Improved Button Interactions */
.btn {
  position: relative;
  overflow: hidden;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  transition: width 0.4s ease, height 0.4s ease;
}

.btn:hover::before {
  width: 200%;
  height: 200%;
}

.btn:focus {
  outline: 3px solid var(--accent-cyan);
  outline-offset: 2px;
}

.btn-primary:hover {
  background: linear-gradient(135deg, #FFD93D 0%, #FFE872 100%);
  box-shadow: var(--shadow-md), 0 0 20px rgba(255, 217, 61, 0.4);
}

.btn-success:hover {
  box-shadow: var(--shadow-md), 0 0 15px rgba(91, 141, 238, 0.3);
}

.btn-danger:hover {
  box-shadow: var(--shadow-md), 0 0 15px rgba(255, 107, 157, 0.3);
}

/* Enhanced Card Hover Effects */
.card {
  position: relative;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.card::after {
  content: '';
  position: absolute;
  inset: 0;
  opacity: 0;
  background: linear-gradient(135deg, rgba(255, 217, 61, 0.1) 0%, transparent 100%);
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.card:hover::after {
  opacity: 1;
}

.card:hover {
  transform: translate(-6px, -6px);
  box-shadow: 10px 10px 0 var(--border-color);
}

/* Smooth Focus States for Inputs */
.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--accent-yellow);
  box-shadow: 0 0 0 3px rgba(255, 217, 61, 0.3), var(--shadow-sm);
  transform: translateY(-1px);
}

/* Resource Item Hover Enhancement */
.resource-item {
  transition: all 0.2s ease;
}

.resource-item:hover {
  background: var(--bg-tertiary);
  transform: translateX(4px);
}

.resource-link {
  transition: all 0.2s ease;
  position: relative;
}

.resource-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-yellow);
  transition: width 0.3s ease;
}

.resource-link:hover::after {
  width: 100%;
}

/* Badge Improvements */
.badge {
  transition: all 0.2s ease;
}

.badge:hover {
  transform: scale(1.05);
}

/* Modal Enhancements */
.modal-overlay.show {
  animation: fadeIn 0.2s ease;
}

.modal-overlay.show .modal {
  animation: slideUp 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px) scale(0.95);
  }

  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* Header Logo Pulse */
.logo-icon {
  transition: all 0.3s ease;
}

.logo:hover .logo-icon {
  transform: rotate(-5deg) scale(1.1);
  box-shadow: 0 0 15px rgba(255, 217, 61, 0.5);
}

/* Filter Pill Improvements */
.filter-pill {
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.filter-pill:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.filter-pill.active {
  animation: pulse 0.3s ease;
  box-shadow: 0 0 0 3px rgba(255, 217, 61, 0.3);
}

/* Search Box Enhancement */
.search-box:focus-within {
  box-shadow: 0 0 0 4px rgba(255, 217, 61, 0.3), var(--shadow-sm);
  border-color: var(--accent-yellow);
}

/* Video Card Improvements */
.video-card {
  transition: all 0.25s ease;
}

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

.video-card:hover .video-title {
  color: var(--accent-purple);
}

/* Table Row Improvements */
.admin-table tbody tr {
  transition: all 0.15s ease;
}

.admin-table tbody tr:hover {
  background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-secondary) 100%);
  transform: scale(1.005);
}

/* Sidebar Navigation Improvements */
.sidebar-nav a {
  transition: all 0.2s ease;
  position: relative;
}

.sidebar-nav a::before {
  content: '';
  position: absolute;
  left: -16px;
  top: 50%;
  width: 4px;
  height: 0;
  background: var(--accent-yellow);
  transform: translateY(-50%);
  transition: height 0.2s ease;
}

.sidebar-nav a:hover::before,
.sidebar-nav a.active::before {
  height: 100%;
}

/* Toast Animation Improvements */
.toast {
  animation: toastIn 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes toastIn {
  from {
    opacity: 0;
    transform: translateX(100px) scale(0.8);
  }

  to {
    opacity: 1;
    transform: translateX(0) scale(1);
  }
}

/* Scroll Indicator */
html {
  scroll-padding-top: 80px;
}

/* Selection Color */
::selection {
  background: var(--accent-yellow);
  color: var(--text-primary);
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 12px;
  height: 12px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
  border-left: 2px solid var(--border-color);
}

::-webkit-scrollbar-thumb {
  background: var(--accent-yellow);
  border: 2px solid var(--border-color);
}

::-webkit-scrollbar-thumb:hover {
  background: #FFED4A;
}

/* Smooth Page Load */
body {
  animation: pageLoad 0.4s ease;
}

@keyframes pageLoad {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

/* Hero Section Enhancement */
.hero {
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: repeating-linear-gradient(45deg,
      transparent,
      transparent 10px,
      rgba(255, 255, 255, 0.03) 10px,
      rgba(255, 255, 255, 0.03) 20px);
  pointer-events: none;
}

/* Footer Enhancement */
footer {
  position: relative;
}

footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-yellow), var(--accent-pink), var(--accent-purple), var(--accent-cyan));
}

/* ===== Touch Feedback Styles ===== */
.touch-active {
  transform: scale(0.97) !important;
  opacity: 0.9;
}

/* ===== Enhanced Mobile Aesthetics ===== */

/* Glassmorphism effect for modals on capable devices */
@supports (backdrop-filter: blur(10px)) {
  .modal-overlay {
    background: rgba(26, 26, 26, 0.4);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
  }
}

/* Enhanced card gradients for premium feel */
.card-header {
  position: relative;
  overflow: hidden;
}

.card-header::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.3) 0%, transparent 60%);
  pointer-events: none;
}

/* Subtle gradient backgrounds for sections */
.main {
  background: linear-gradient(180deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  min-height: calc(100vh - 200px);
}

/* Premium badge styling */
.badge {
  position: relative;
  overflow: hidden;
}

.badge::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
  animation: shimmer 3s ease-in-out infinite;
}

/* Stats bar gradient enhancement */
.stats-bar {
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
  position: relative;
}

.stats-bar::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-yellow), var(--accent-green), var(--accent-cyan));
}

/* Stat value pulse animation on load */
.stat-value {
  animation: countUp 0.8s ease forwards;
}

@keyframes countUp {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Search box refinement */
.search-box {
  position: relative;
}

.search-box::before {
  content: '';
  position: absolute;
  inset: -2px;
  background: linear-gradient(135deg, var(--accent-yellow), var(--accent-cyan));
  opacity: 0;
  z-index: -1;
  transition: opacity 0.3s ease;
}

.search-box:focus-within::before {
  opacity: 0.3;
}

/* Filter pills gradient effect */
.filter-pill.active {
  background: linear-gradient(135deg, var(--accent-yellow) 0%, #FFE872 100%);
}

/* Video card premium hover */
.video-card {
  position: relative;
}

.video-card::before {
  content: '▶';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0);
  font-size: 3rem;
  color: white;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
  opacity: 0;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 10;
  pointer-events: none;
}

.video-card:hover::before {
  transform: translate(-50%, -80%) scale(1);
  opacity: 1;
}

/* Course header gradient bar */
.course-header {
  position: relative;
  overflow: hidden;
}

.course-header::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg,
      var(--accent-yellow) 0%,
      var(--accent-green) 25%,
      var(--accent-cyan) 50%,
      var(--accent-purple) 75%,
      var(--accent-pink) 100%);
}

/* Empty state enhancement */
.empty-state-icon {
  animation: float 3s ease-in-out infinite;
}

@keyframes float {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-10px);
  }
}

/* Resource icon pulse */
.resource-icon {
  transition: all 0.3s ease;
}

.resource-item:hover .resource-icon {
  transform: scale(1.1) rotate(-5deg);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

/* Login card premium feel */
.login-card {
  position: relative;
  overflow: hidden;
}

.login-card::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(255, 217, 61, 0.1) 0%, transparent 60%);
  animation: pulse 4s ease-in-out infinite;
  pointer-events: none;
}

/* Mobile-first button refinements */
@media (max-width: 768px) {
  .btn {
    position: relative;
    overflow: hidden;
  }

  /* Gradient border effect on focus for accessibility */
  .btn:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px var(--accent-cyan);
  }

  /* Cards get subtle shadow on touch screens since hover doesn't work */
  .card {
    box-shadow: var(--shadow-md);
  }

  /* Video embed touch indicator */
  .video-embed {
    position: relative;
  }

  .video-embed::after {
    content: '📺 Tap to play';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 8px;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.7), transparent);
    color: white;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    text-align: center;
    opacity: 0.8;
    pointer-events: none;
  }

  /* Better tap target indicators */
  .nav-links a:active,
  .btn:active,
  .filter-pill:active,
  .card:active {
    outline: 2px solid var(--accent-yellow);
    outline-offset: 2px;
  }
}

/* Dark mode refinements for mobile */
[data-theme="dark"] .main {
  background: linear-gradient(180deg, var(--bg-primary) 0%, #252525 100%);
}

[data-theme="dark"] .stats-bar {
  background: linear-gradient(135deg, var(--bg-secondary) 0%, #353535 100%);
}

[data-theme="dark"] .modal-overlay {
  background: rgba(0, 0, 0, 0.6);
}

/* Accessibility: High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --shadow-sm: 3px 3px 0 #000;
    --shadow-md: 5px 5px 0 #000;
    --shadow-lg: 7px 7px 0 #000;
    --border-thick: 3px solid #000;
    --border-extra: 4px solid #000;
  }

  .btn,
  .card,
  .filter-pill,
  .nav-links a {
    border-width: 3px;
  }
}

/* iOS Safari specific fixes */
@supports (-webkit-touch-callout: none) {

  /* Fix for iOS momentum scrolling */
  .filter-pills,
  .stats-bar,
  .admin-table {
    -webkit-overflow-scrolling: touch;
  }

  /* Fix for iOS input zoom */
  input,
  select,
  textarea {
    font-size: 16px !important;
  }

  /* Fix for iOS 100vh issue */
  .login-container {
    min-height: -webkit-fill-available;
  }
}

/* Android specific enhancements */
@media screen and (-webkit-min-device-pixel-ratio: 0) and (min-resolution: .001dpcm) {

  /* Better font rendering on Android */
  body {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }
}

/* Print-friendly badge colors */
@media print {

  .badge-semester,
  .badge-subject {
    background: white !important;
    color: black !important;
    border: 2px solid black !important;
  }
}

/* ===== Quality of Life Enhancements v3.0 ===== */

/* Scroll to Top Button */
.scroll-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 48px;
  height: 48px;
  background: var(--accent-yellow);
  border: var(--border-thick);
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all var(--transition-smooth);
  z-index: var(--z-toast);
}

.scroll-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.scroll-to-top:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  background: var(--accent-yellow-light);
}

.scroll-to-top:active {
  transform: translateY(0);
}

/* Breadcrumb Navigation */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  margin-bottom: var(--space-lg);
  flex-wrap: wrap;
}

.breadcrumb a {
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.breadcrumb a:hover {
  color: var(--accent-purple);
}

.breadcrumb-separator {
  color: var(--text-muted);
}

.breadcrumb-current {
  color: var(--text-primary);
  font-weight: 600;
}

/* Improved Progress Bar */
.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--bg-secondary);
  border: var(--border-thin);
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: var(--gradient-green);
  transition: width 0.5s ease;
}

/* Better Focus States */
*:focus-visible {
  outline: 3px solid var(--accent-cyan);
  outline-offset: 2px;
}

/* Skip Link for Accessibility */
.skip-link {
  position: absolute;
  top: -100%;
  left: 50%;
  transform: translateX(-50%);
  background: var(--text-primary);
  color: var(--bg-primary);
  padding: var(--space-sm) var(--space-lg);
  font-family: var(--font-mono);
  font-weight: 600;
  z-index: var(--z-loader);
  transition: top 0.3s ease;
}

.skip-link:focus {
  top: var(--space-sm);
}

/* Refined Loading Skeleton */
.skeleton-loading {
  background: linear-gradient(90deg,
      var(--bg-secondary) 0%,
      var(--bg-tertiary) 50%,
      var(--bg-secondary) 100%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s ease-in-out infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-shimmer {
  0% {
    background-position: 200% 0;
  }

  100% {
    background-position: -200% 0;
  }
}

/* Tooltip */
.tooltip {
  position: relative;
  cursor: help;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-4px);
  padding: var(--space-xs) var(--space-sm);
  background: var(--text-primary);
  color: var(--bg-primary);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  white-space: nowrap;
  border-radius: var(--radius-sm);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-fast);
  pointer-events: none;
  z-index: var(--z-dropdown);
}

.tooltip:hover::after {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(-8px);
}

/* Notification Badge */
.notification-badge {
  position: absolute;
  top: -6px;
  right: -6px;
  min-width: 18px;
  height: 18px;
  background: var(--accent-red);
  color: white;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  border: 2px solid var(--bg-primary);
}

/* Refined Card Variants */
.card-compact {
  padding: var(--space-md);
}

.card-featured {
  border-left: 4px solid var(--accent-purple);
  position: relative;
}

.card-featured::before {
  content: '★';
  position: absolute;
  top: -8px;
  right: var(--space-md);
  background: var(--accent-yellow);
  padding: 2px 8px;
  font-size: 0.75rem;
  border: var(--border-thin);
}

/* Better Mobile Grid */
@media (max-width: 480px) {
  .course-grid {
    gap: var(--space-md);
  }

  .card {
    box-shadow: var(--shadow-sm);
  }

  .scroll-to-top {
    bottom: 1rem;
    right: 1rem;
    width: 44px;
    height: 44px;
  }
}

/* Improved Footer v2 */
.footer {
  position: relative;
  background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg,
      var(--accent-yellow) 0%,
      var(--accent-orange) 25%,
      var(--accent-pink) 50%,
      var(--accent-purple) 75%,
      var(--accent-cyan) 100%);
}

.footer-bottom {
  margin-top: var(--space-lg);
  padding-top: var(--space-md);
  border-top: 1px solid rgba(0, 0, 0, 0.1);
  text-align: center;
}

/* Pulse animation for important elements */
.pulse-attention {
  animation: pulse-attention 2s ease-in-out infinite;
}

@keyframes pulse-attention {

  0%,
  100% {
    box-shadow: var(--shadow-sm);
  }

  50% {
    box-shadow: var(--shadow-sm), 0 0 0 4px rgba(251, 191, 36, 0.3);
  }
}

/* Success/Error States */
.state-success {
  background: var(--accent-green-light) !important;
  border-color: var(--accent-green) !important;
}

.state-error {
  background: var(--accent-pink-light) !important;
  border-color: var(--accent-pink) !important;
}

/* Smooth page transitions */
.page-enter {
  animation: page-fade-in 0.4s ease forwards;
}

@keyframes page-fade-in {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}