/* CS5008 Learning Guide - Creative Design System v2 */
/* Inspired by: Duolingo gamification, terminal aesthetics, compiler journey */

/* ============================================
   Custom Fonts (Google Fonts)
   ============================================ */
@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&family=Inter:wght@400;500;600;700&display=swap');

/* ============================================
   CSS Custom Properties - Unique Palette
   ============================================ */
:root {
  /* Midnight Code Theme (Default) */
  --bg-base: #0a0a0f;
  --bg-elevated: #12121a;
  --bg-card: #1a1a24;
  --bg-card-hover: #222230;
  --bg-terminal: #0d1117;

  --text-primary: #e6e6e6;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;

  /* Vibrant Gradients - Purple/Cyan/Green tech palette */
  --gradient-primary: linear-gradient(135deg, #7c3aed 0%, #06b6d4 100%);
  --gradient-secondary: linear-gradient(135deg, #10b981 0%, #3b82f6 100%);
  --gradient-accent: linear-gradient(135deg, #f59e0b 0%, #ef4444 100%);
  --gradient-card: linear-gradient(145deg, rgba(124, 58, 237, 0.1) 0%, rgba(6, 182, 212, 0.05) 100%);

  /* Accent Colors */
  --accent-purple: #7c3aed;
  --accent-cyan: #06b6d4;
  --accent-green: #10b981;
  --accent-yellow: #fbbf24;
  --accent-red: #ef4444;
  --accent-pink: #ec4899;

  /* Semantic Colors */
  --color-locked: #4b5563;
  --color-unlocked: var(--accent-cyan);
  --color-complete: var(--accent-green);
  --color-xp: var(--accent-yellow);

  /* Borders */
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-default: rgba(255, 255, 255, 0.1);
  --border-glow: rgba(124, 58, 237, 0.4);

  /* Terminal Colors */
  --terminal-green: #4ade80;
  --terminal-blue: #60a5fa;
  --terminal-yellow: #fde047;
  --terminal-red: #f87171;
  --terminal-prompt: #c084fc;

  /* Shadows & Glows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.6);
  --shadow-glow-purple: 0 0 30px rgba(124, 58, 237, 0.3);
  --shadow-glow-cyan: 0 0 30px rgba(6, 182, 212, 0.3);
  --shadow-glow-green: 0 0 30px rgba(16, 185, 129, 0.3);

  /* Spacing */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;
  --space-20: 80px;

  /* Border Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-2xl: 32px;
  --radius-full: 9999px;

  /* Typography */
  --font-display: 'Space Grotesk', system-ui, sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Animation */
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out-back: cubic-bezier(0.34, 1.56, 0.64, 1);
  --transition-fast: 150ms var(--ease-out-expo);
  --transition-normal: 300ms var(--ease-out-expo);
  --transition-slow: 500ms var(--ease-out-expo);
}

/* Light Theme - Minimal, high contrast */
[data-theme="light"] {
  --bg-base: #fafafa;
  --bg-elevated: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f5f5f5;
  --bg-terminal: #1e1e1e;

  --text-primary: #111827;
  --text-secondary: #4b5563;
  --text-muted: #9ca3af;

  --border-subtle: rgba(0, 0, 0, 0.04);
  --border-default: rgba(0, 0, 0, 0.08);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.16);
}

/* Light Theme - Code block overrides (keep light text on dark terminal bg) */
[data-theme="light"] pre,
[data-theme="light"] code {
  color: #e6e6e6;
  border-color: rgba(255, 255, 255, 0.1);
}

[data-theme="light"] pre code {
  color: #e6e6e6;
}

[data-theme="light"] code {
  color: #4ade80;
}

/* Light Theme - Fix ALL dark background containers (terminal-style callouts, etc.) */
[data-theme="light"] [style*="bg-terminal"],
[data-theme="light"] [style*="--bg-terminal"],
[data-theme="light"] .terminal-box,
[data-theme="light"] .hero-terminal {
  color: #e6e6e6;
}

[data-theme="light"] [style*="bg-terminal"] *,
[data-theme="light"] [style*="--bg-terminal"] * {
  color: inherit;
}

/* Force light text on any element using inline style with bg-terminal */
[data-theme="light"] [style*="background: var(--bg-terminal)"],
[data-theme="light"] [style*="background:var(--bg-terminal)"] {
  color: #e6e6e6 !important;
}

[data-theme="light"] [style*="background: var(--bg-terminal)"] span,
[data-theme="light"] [style*="background: var(--bg-terminal)"] li,
[data-theme="light"] [style*="background: var(--bg-terminal)"] strong,
[data-theme="light"] [style*="background: var(--bg-terminal)"] p,
[data-theme="light"] [style*="background: var(--bg-terminal)"] div {
  color: #e6e6e6 !important;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

/* Animated Background Grid */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(124, 58, 237, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(124, 58, 237, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  z-index: -1;
}

/* Floating Orbs (ambient decoration) */
.orb {
  position: fixed;
  border-radius: 50%;
  filter: blur(80px);
  pointer-events: none;
  z-index: -1;
  opacity: 0.5;
  animation: float 20s infinite ease-in-out;
}

.orb-1 {
  width: 400px;
  height: 400px;
  background: var(--accent-purple);
  top: -100px;
  right: -100px;
  animation-delay: 0s;
}

.orb-2 {
  width: 300px;
  height: 300px;
  background: var(--accent-cyan);
  bottom: -50px;
  left: -100px;
  animation-delay: -10s;
}

.orb-3 {
  width: 200px;
  height: 200px;
  background: var(--accent-green);
  top: 50%;
  left: 50%;
  animation-delay: -5s;
}

@keyframes float {

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

  33% {
    transform: translate(30px, -30px) scale(1.1);
  }

  66% {
    transform: translate(-20px, 20px) scale(0.9);
  }
}

/* Selection */
::selection {
  background: rgba(124, 58, 237, 0.4);
  color: white;
}

/* ============================================
   Typography
   ============================================ */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
}

h2 {
  font-size: clamp(1.75rem, 3vw, 2.5rem);
}

h3 {
  font-size: clamp(1.25rem, 2vw, 1.75rem);
}

h4 {
  font-size: 1.25rem;
}

p {
  color: var(--text-secondary);
  max-width: 65ch;
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
  transition: all var(--transition-fast);
}

a:hover {
  color: var(--accent-purple);
  text-decoration: underline;
  text-decoration-style: wavy;
  text-underline-offset: 4px;
}

/* Code & Terminal Style */
code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--bg-terminal);
  color: var(--terminal-green);
  padding: 0.2em 0.5em;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-default);
}

pre {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  background: var(--bg-terminal);
  color: var(--text-primary);
  padding: var(--space-6);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-default);
  overflow-x: auto;
  position: relative;
}

/* Terminal Header */
pre::before {
  content: '';
  position: absolute;
  top: 12px;
  left: 16px;
  width: 12px;
  height: 12px;
  background: var(--accent-red);
  border-radius: 50%;
  box-shadow:
    20px 0 0 var(--accent-yellow),
    40px 0 0 var(--accent-green);
}

pre code {
  background: none;
  border: none;
  padding: 0;
  color: inherit;
  display: block;
  margin-top: var(--space-6);
}

/* ============================================
   Header - Floating Glass Nav
   ============================================ */
.header {
  position: fixed;
  top: var(--space-4);
  left: 50%;
  transform: translateX(-50%);
  z-index: 100;
  width: calc(100% - var(--space-8));
  max-width: 1200px;
}

.header-content {
  background: rgba(26, 26, 36, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: var(--space-3) var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  box-shadow: var(--shadow-lg);
}

[data-theme="light"] .header-content {
  background: rgba(255, 255, 255, 0.8);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--text-primary);
  text-decoration: none;
}

.logo:hover {
  text-decoration: none;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--gradient-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  box-shadow: var(--shadow-glow-purple);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* XP Badge */
.xp-badge {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(251, 191, 36, 0.1);
  border: 1px solid rgba(251, 191, 36, 0.3);
  border-radius: var(--radius-full);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--accent-yellow);
}

.xp-badge::before {
  content: '⚡';
}

/* Streak Badge */
.streak-badge {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.3);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--accent-red);
}

.streak-badge::before {
  content: '🔥';
}

/* Search Button */
.search-btn {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-full);
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.875rem;
  transition: all var(--transition-fast);
}

.search-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-purple);
  color: var(--text-primary);
}

.search-btn kbd {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 2px 6px;
  background: var(--bg-base);
  border-radius: var(--radius-sm);
  margin-left: var(--space-2);
}

/* Theme Toggle */
.theme-toggle {
  width: 40px;
  height: 40px;
  border: 1px solid var(--border-default);
  background: var(--bg-card);
  border-radius: var(--radius-full);
  cursor: pointer;
  font-size: 1.25rem;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  transform: rotate(15deg) scale(1.1);
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-glow-purple);
}

/* ============================================
   Main Container
   ============================================ */
.main-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: calc(100px + var(--space-8)) var(--space-6) var(--space-16);
}

/* ============================================
   Hero Section - Compiler Journey Theme
   ============================================ */
.hero {
  text-align: center;
  padding: var(--space-16) 0;
  position: relative;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(124, 58, 237, 0.1);
  border: 1px solid rgba(124, 58, 237, 0.3);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  color: var(--accent-purple);
  margin-bottom: var(--space-6);
  animation: pulse 2s infinite;
}

@keyframes pulse {

  0%,
  100% {
    box-shadow: 0 0 0 0 rgba(124, 58, 237, 0.4);
  }

  50% {
    box-shadow: 0 0 0 10px rgba(124, 58, 237, 0);
  }
}

.hero h1 {
  margin-bottom: var(--space-4);
}

.hero h1 span {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto var(--space-8);
  text-align: center;
  line-height: 1.6;
}

/* Terminal-style tagline */
.hero-terminal {
  display: inline-block;
  background: var(--bg-terminal);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: var(--space-4) var(--space-6);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  margin-bottom: var(--space-10);
  position: relative;
  text-align: left;
}

.hero-terminal::before {
  content: '$ ';
  color: var(--terminal-prompt);
}

.hero-terminal .typing {
  color: var(--terminal-green);
  border-right: 2px solid var(--terminal-green);
  animation: blink 1s infinite;
}

@keyframes blink {

  0%,
  50% {
    border-color: var(--terminal-green);
  }

  51%,
  100% {
    border-color: transparent;
  }
}

/* Stats Grid */
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-4);
  max-width: 800px;
  margin: 0 auto;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  text-align: center;
  transition: all var(--transition-normal);
}

.stat-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-glow-purple);
}

.stat-icon {
  font-size: 2rem;
  margin-bottom: var(--space-2);
}

.stat-value {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ============================================
   Journey Path - Visual Timeline
   ============================================ */
.journey-section {
  margin: var(--space-16) 0;
}

.journey-section h2 {
  text-align: center;
  margin-bottom: var(--space-4);
}

.journey-section .section-subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: var(--space-10);
}

/* Module Grid with Journey Line */
.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: var(--space-6);
  position: relative;
}

/* ============================================
   Module Cards - Creative Design
   ============================================ */
.module-card {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  position: relative;
  overflow: hidden;
  cursor: pointer;
  transition: all var(--transition-normal);

  /* Subtle gradient overlay */
  background-image: var(--gradient-card);
}

.module-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.module-card:hover {
  transform: translateY(-6px) scale(1.01);
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-lg), var(--shadow-glow-purple);
}

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

/* Card States */
.module-card.locked {
  opacity: 0.6;
}

.module-card.locked::after {
  content: '🔒';
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  font-size: 1.5rem;
  filter: grayscale(1);
}

.module-card.unlocked::before {
  opacity: 1;
  background: var(--gradient-secondary);
}

.module-card.completed {
  border-color: var(--accent-green);
}

.module-card.completed::before {
  opacity: 1;
  background: linear-gradient(90deg, var(--accent-green), var(--accent-cyan));
}

.module-card.completed::after {
  content: '✨';
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  font-size: 1.5rem;
  animation: sparkle 1s infinite;
}

@keyframes sparkle {

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

  50% {
    transform: scale(1.2) rotate(10deg);
  }
}

/* Module Number Badge */
.module-number {
  position: absolute;
  top: var(--space-4);
  left: var(--space-4);
  width: 32px;
  height: 32px;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.875rem;
  color: white;
  box-shadow: var(--shadow-glow-purple);
}

.module-card.completed .module-number {
  background: var(--accent-green);
  box-shadow: var(--shadow-glow-green);
}

/* Module Content */
.module-content {
  padding-left: 48px;
}

.module-week {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-2);
}

.module-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: var(--text-primary);
  transition: color var(--transition-fast);
}

.module-card:hover .module-title {
  color: var(--accent-cyan);
}

.module-description {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
  line-height: 1.5;
}

/* Tags */
.module-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.module-tag {
  font-size: 0.75rem;
  padding: var(--space-1) var(--space-3);
  background: rgba(6, 182, 212, 0.1);
  border: 1px solid rgba(6, 182, 212, 0.2);
  border-radius: var(--radius-full);
  color: var(--accent-cyan);
}

/* Meta info */
.module-meta {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.module-meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

/* XP Reward */
.module-xp {
  margin-left: auto;
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--accent-yellow);
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.module-xp::before {
  content: '⚡';
}

/* Progress Bar */
.progress-bar {
  height: 6px;
  background: var(--border-subtle);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-top: var(--space-4);
}

.progress-bar-fill {
  height: 100%;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  transition: width 500ms var(--ease-out-expo);
  position: relative;
}

.progress-bar-fill::after {
  content: '';
  position: absolute;
  right: 0;
  top: 0;
  bottom: 0;
  width: 20px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3));
  animation: shimmer 2s infinite;
}

@keyframes shimmer {
  0% {
    transform: translateX(-100%);
  }

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

/* Lock Overlay */
.lock-overlay {
  position: absolute;
  inset: 0;
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(8px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
  opacity: 0;
  transition: opacity var(--transition-normal);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
}

.module-card.locked:hover .lock-overlay {
  opacity: 1;
}

.lock-icon {
  font-size: 3rem;
  animation: wiggle 0.5s ease-in-out;
}

@keyframes wiggle {

  0%,
  100% {
    transform: rotate(0deg);
  }

  25% {
    transform: rotate(-10deg);
  }

  75% {
    transform: rotate(10deg);
  }
}

.unlock-input {
  width: 100%;
  max-width: 200px;
  padding: var(--space-3) var(--space-4);
  background: var(--bg-terminal);
  border: 2px solid var(--border-default);
  border-radius: var(--radius-md);
  color: var(--terminal-green);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  text-align: center;
  transition: all var(--transition-fast);
}

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

.unlock-input:focus {
  outline: none;
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-glow-purple);
}

.unlock-btn {
  padding: var(--space-3) var(--space-6);
  background: var(--gradient-primary);
  border: none;
  border-radius: var(--radius-md);
  color: white;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.unlock-btn:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-glow-purple);
}

.unlock-error {
  color: var(--accent-red);
  font-size: 0.85rem;
  display: none;
}

.unlock-error.show {
  display: block;
  animation: shake 0.5s ease-in-out;
}

@keyframes shake {

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

  20%,
  60% {
    transform: translateX(-8px);
  }

  40%,
  80% {
    transform: translateX(8px);
  }
}

/* ============================================
   Search Modal
   ============================================ */
.search-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(10, 10, 15, 0.8);
  backdrop-filter: blur(12px);
  z-index: 200;
  display: none;
  align-items: flex-start;
  justify-content: center;
  padding-top: 15vh;
  animation: fadeIn 200ms ease-out;
}

.search-backdrop.open {
  display: flex;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

.search-modal {
  width: 100%;
  max-width: 600px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg), var(--shadow-glow-purple);
  overflow: hidden;
  animation: slideDown 300ms var(--ease-out-expo);
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-20px) scale(0.95);
  }

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

.search-input-wrapper {
  display: flex;
  align-items: center;
  padding: var(--space-5);
  border-bottom: 1px solid var(--border-subtle);
  gap: var(--space-4);
}

.search-input {
  flex: 1;
  background: none;
  border: none;
  font-family: var(--font-body);
  font-size: 1.125rem;
  color: var(--text-primary);
  outline: none;
}

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

.search-results {
  max-height: 400px;
  overflow-y: auto;
  padding: var(--space-3);
}

.search-result {
  padding: var(--space-4);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.search-result:hover {
  background: var(--bg-card);
}

.search-result-title {
  font-weight: 600;
  margin-bottom: var(--space-1);
}

.search-result-snippet {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.search-result-snippet mark {
  background: rgba(124, 58, 237, 0.3);
  color: var(--text-primary);
  padding: 0 4px;
  border-radius: 2px;
}

.search-empty {
  padding: var(--space-10);
  text-align: center;
  color: var(--text-muted);
}

/* ============================================
   Continue Banner
   ============================================ */
.continue-banner {
  display: none;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
  background: linear-gradient(90deg, rgba(124, 58, 237, 0.1), rgba(6, 182, 212, 0.1));
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: var(--space-5) var(--space-8);
  margin-bottom: var(--space-8);
  animation: slideIn 500ms var(--ease-out-expo);
}

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

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

.continue-banner a {
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.continue-banner a::after {
  content: '→';
  transition: transform var(--transition-fast);
}

.continue-banner a:hover::after {
  transform: translateX(4px);
}

/* ============================================
   Quiz Component
   ============================================ */
.quiz {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  margin: var(--space-6) 0;
  position: relative;
  overflow: hidden;
}

.quiz::before {
  content: '🧠';
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  font-size: 1.5rem;
  opacity: 0.5;
}

.quiz-question {
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: var(--space-5);
  padding-right: 40px;
}

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.quiz-option {
  padding: var(--space-4);
  background: var(--bg-elevated);
  border: 2px solid var(--border-default);
  border-radius: var(--radius-lg);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: var(--space-4);
  transition: all var(--transition-fast);
}

.quiz-option:hover {
  border-color: var(--accent-purple);
  background: rgba(124, 58, 237, 0.05);
  transform: translateX(4px);
}

.quiz-option.selected {
  border-color: var(--accent-cyan);
  background: rgba(6, 182, 212, 0.1);
}

.quiz-option.correct {
  border-color: var(--accent-green);
  background: rgba(16, 185, 129, 0.1);
}

.quiz-option.correct::before {
  content: '✅';
  margin-right: var(--space-2);
}

.quiz-option.incorrect {
  border-color: var(--accent-red);
  background: rgba(239, 68, 68, 0.1);
}

.quiz-option.incorrect::before {
  content: '❌';
  margin-right: var(--space-2);
}

.quiz-radio {
  width: 22px;
  height: 22px;
  border: 2px solid var(--text-muted);
  border-radius: var(--radius-full);
  flex-shrink: 0;
  transition: all var(--transition-fast);
}

.quiz-option:hover .quiz-radio {
  border-color: var(--accent-purple);
}

.quiz-option.selected .quiz-radio {
  border-color: var(--accent-cyan);
  background: var(--accent-cyan);
  box-shadow: inset 0 0 0 4px var(--bg-card);
}

.quiz-feedback {
  margin-top: var(--space-5);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  display: none;
  font-weight: 500;
}

.quiz-feedback.show {
  display: block;
  animation: slideIn 300ms var(--ease-out-expo);
}

.quiz-feedback.correct {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid var(--accent-green);
  color: var(--accent-green);
}

.quiz-feedback.incorrect {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid var(--accent-red);
  color: var(--accent-red);
}

/* ============================================
   Section Component (Collapsible)
   ============================================ */
.section {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  margin-bottom: var(--space-4);
  overflow: hidden;
  transition: all var(--transition-normal);
}

.section:hover {
  border-color: var(--border-glow);
}

.section-header {
  padding: var(--space-5) var(--space-6);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: background var(--transition-fast);
}

.section-header:hover {
  background: var(--bg-card-hover);
}

.section-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  margin: 0;
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.section-toggle {
  font-size: 1.25rem;
  color: var(--accent-purple);
  transition: transform var(--transition-normal);
}

.section.open .section-toggle {
  transform: rotate(90deg);
}

.section-content {
  padding: 0 var(--space-6) var(--space-6);
  display: none;
  animation: expand 300ms var(--ease-out-expo);
}

.section.open .section-content {
  display: block;
}

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

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

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 768px) {
  .header {
    top: var(--space-2);
    width: calc(100% - var(--space-4));
  }

  .header-content {
    padding: var(--space-2) var(--space-4);
  }

  .xp-badge,
  .streak-badge {
    display: none;
  }

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

  .module-grid {
    grid-template-columns: 1fr;
  }

  .main-container {
    padding-left: var(--space-4);
    padding-right: var(--space-4);
  }
}

/* ============================================
   Utility Classes
   ============================================ */
.mt-4 {
  margin-top: var(--space-4);
}

.mt-6 {
  margin-top: var(--space-6);
}

.mt-8 {
  margin-top: var(--space-8);
}

.mb-4 {
  margin-bottom: var(--space-4);
}

.mb-6 {
  margin-bottom: var(--space-6);
}

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

.text-gradient {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ============================================
   TA-Only Protected Content
   ============================================ */
.ta-only-content {
  display: none;
  margin: var(--space-6) 0;
  padding: var(--space-6);
  background: linear-gradient(145deg, rgba(239, 68, 68, 0.05), rgba(124, 58, 237, 0.05));
  border: 2px dashed rgba(239, 68, 68, 0.3);
  border-radius: var(--radius-xl);
  position: relative;
}

.ta-only-content.unlocked {
  display: block;
  border-style: solid;
  border-color: var(--accent-green);
  background: linear-gradient(145deg, rgba(16, 185, 129, 0.05), rgba(6, 182, 212, 0.05));
}

.ta-only-content::before {
  content: '🔐 TA Access Required';
  position: absolute;
  top: -12px;
  left: var(--space-4);
  padding: var(--space-1) var(--space-3);
  background: var(--bg-base);
  border: 1px solid var(--accent-red);
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent-red);
}

.ta-only-content.unlocked::before {
  content: '✅ TA Content Unlocked';
  border-color: var(--accent-green);
  color: var(--accent-green);
}

.ta-only-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
  font-family: var(--font-display);
  font-weight: 600;
  color: var(--text-primary);
}

.ta-only-header span {
  font-size: 1.25rem;
}

.ta-only-content pre {
  margin-bottom: 0;
}

/* Locked placeholder */
.ta-locked-placeholder {
  text-align: center;
  padding: var(--space-8);
  color: var(--text-muted);
}

.ta-locked-placeholder p {
  margin: 0 auto;
}

/* ============================================
   Module Page Utilities
   Refactored from inline styles
   ============================================ */

/* Page Container */
.module-page {
  max-width: 900px;
}

/* Breadcrumb Navigation */
.breadcrumb {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: var(--space-6);
}

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

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

/* Module Header */
.module-header {
  margin-bottom: var(--space-10);
}

.module-header h1 {
  margin-bottom: var(--space-3);
}

.module-header p {
  font-size: 1.1rem;
  max-width: 600px;
}

.module-header-meta {
  display: flex;
  gap: var(--space-4);
  margin-top: var(--space-4);
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Module Badge */
.module-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2) var(--space-4);
  background: rgba(124, 58, 237, 0.1);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  color: var(--accent-purple);
  margin-bottom: var(--space-4);
}

.module-badge.orange {
  background: rgba(245, 158, 11, 0.1);
  color: var(--accent-yellow);
}

.module-badge.green {
  background: rgba(16, 185, 129, 0.1);
  color: var(--accent-green);
}

/* Step Cards (for Fetch-Decode-Execute, etc.) */
.step-card {
  display: flex;
  gap: var(--space-4);
  align-items: flex-start;
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}

.step-card-number {
  width: 48px;
  height: 48px;
  background: var(--gradient-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  flex-shrink: 0;
}

.step-card-title {
  font-weight: 600;
  margin-bottom: var(--space-1);
}

.step-card-description {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Grid Layouts */
.grid-stack {
  display: grid;
  gap: var(--space-4);
}

.grid-stack.lg {
  gap: var(--space-6);
}

/* Tables */
.data-table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-4) 0;
  font-size: 0.9rem;
}

.data-table th,
.data-table td {
  padding: var(--space-2) var(--space-3);
  text-align: left;
  border: 1px solid var(--border-default);
}

.data-table th {
  background: var(--bg-card);
  font-weight: 600;
}

.data-table tr:hover {
  background: rgba(124, 58, 237, 0.05);
}

/* Callout Boxes */
.callout {
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  margin: var(--space-6) 0;
}

.callout.terminal {
  background: var(--bg-terminal);
  border: 1px solid var(--border-default);
}

.callout.info {
  background: rgba(6, 182, 212, 0.1);
  border: 1px solid var(--accent-cyan);
}

.callout.success {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid var(--accent-green);
}

.callout.warning {
  background: rgba(245, 158, 11, 0.1);
  border: 1px solid var(--accent-yellow);
}

.callout.highlight {
  background: rgba(124, 58, 237, 0.1);
  border: 1px solid var(--accent-purple);
}

.callout-title {
  font-weight: 600;
  margin-bottom: var(--space-3);
}

.callout-title.cyan {
  color: var(--accent-cyan);
}

.callout-title.green {
  color: var(--accent-green);
}

.callout-title.yellow {
  color: var(--accent-yellow);
}

.callout-title.purple {
  color: var(--accent-purple);
}

/* Module Navigation Footer */
.module-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-6);
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-default);
  margin-top: var(--space-10);
}

.module-nav-prev {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--text-secondary);
}

.module-nav-next {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-5);
  background: var(--gradient-primary);
  color: white;
  border-radius: var(--radius-md);
  font-weight: 600;
}

.module-nav-next:hover {
  text-decoration: none;
  filter: brightness(1.1);
}

/* Spacing Utilities */
.mt-4 {
  margin-top: var(--space-4);
}

.mt-6 {
  margin-top: var(--space-6);
}

.mt-8 {
  margin-top: var(--space-8);
}

.mb-3 {
  margin-bottom: var(--space-3);
}

.mb-4 {
  margin-bottom: var(--space-4);
}

.mb-6 {
  margin-bottom: var(--space-6);
}

/* Text Utilities */
.text-muted {
  color: var(--text-muted);
}

.text-secondary {
  color: var(--text-secondary);
}

.text-small {
  font-size: 0.9rem;
}

.text-mono {
  font-family: var(--font-mono);
}

.font-semibold {
  font-weight: 600;
}

/* Flex Utilities */
.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

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

.items-start {
  align-items: flex-start;
}

.justify-between {
  justify-content: space-between;
}

.gap-2 {
  gap: var(--space-2);
}

.gap-3 {
  gap: var(--space-3);
}

.gap-4 {
  gap: var(--space-4);
}