/* ============================================
   LMS Demo - Shared Stylesheet
   Modern, responsive design with microanimations
   ============================================ */

:root {
  /* Business Bold Neo-Brutal-Lite Color Palette */
  --ink: #111827;
  --surface: #FFFFFF;
  --surface-off: #F8FAFC;
  --primary-cta: #1D4ED8;
  --primary-hover: #1e40af;
  --secondary: #334155;
  --accent-amber: #D97706;
  --success: #15803D;
  --warning: #B45309;
  --danger: #B91C1C;
  --divider: #E2E8F0;
  
  /* Base colors */
  --secondary-color: #64748b;
  --secondary-hover: #475569;
  --bg-color: #F8FAFC;
  --card-bg: #FFFFFF;
  --text-primary: #111827;
  --text-secondary: #64748b;
  --border-color: #111827;
  --success-color: #15803D;
  
  /* Neo-Brutal Shadows (hard, offset) - Subtle */
  --shadow-sm: 2px 2px 0 0 var(--ink);
  --shadow-md: 3px 3px 0 0 var(--ink);
  --shadow-lg: 4px 4px 0 0 var(--ink);
  
  --radius: 0;
  --radius-sm: 0;
  --transition: all 0.2s ease;
  
  /* Border thickness - Subtle */
  --border-thick: 2px;
  --border-medium: 1.5px;
}

/* Digital Twins - Professional Blue Theme (Adaptable-aligned) */
:root,
body[data-topic="digital-twins"] {
  --primary-color: #0ea5e9;
  --primary-hover: #0284c7;
  --primary-light: #38bdf8;
  --primary-rgb: 14, 165, 233;
  --hero-gradient: linear-gradient(135deg, #0ea5e9 0%, #0284c7 100%);
  --accent-color: #06b6d4;
  --accent-light: #22d3ee;
  --radius: 0;
  --radius-sm: 0;
}

/* Remove rounded borders for Digital Twins */
body[data-topic="digital-twins"] .card,
body[data-topic="digital-twins"] .btn,
body[data-topic="digital-twins"] .tag,
body[data-topic="digital-twins"] .progress-bar-container,
body[data-topic="digital-twins"] .progress-bar,
body[data-topic="digital-twins"] .module-check,
body[data-topic="digital-twins"] .kpi-card,
body[data-topic="digital-twins"] .video-container,
body[data-topic="digital-twins"] .video-placeholder,
body[data-topic="digital-twins"] .play-button,
body[data-topic="digital-twins"] .lesson-item,
body[data-topic="digital-twins"] .lesson-number,
body[data-topic="digital-twins"] .exam-header,
body[data-topic="digital-twins"] .question-card,
body[data-topic="digital-twins"] .answer-option,
body[data-topic="digital-twins"] .answer-label,
body[data-topic="digital-twins"] .question-btn,
body[data-topic="digital-twins"] .legend-color,
body[data-topic="digital-twins"] code {
  border-radius: 0 !important;
}

/* All pages use same colors as Digital Twins */
body[data-topic="html-css"],
body[data-topic="ar-vr"] {
  --primary-color: #1D4ED8;
  --primary-hover: #1e40af;
  --primary-light: #3b82f6;
  --primary-rgb: 29, 78, 216;
  --hero-gradient: linear-gradient(135deg, #1D4ED8 0%, #1e40af 100%);
  --accent-color: #D97706;
  --accent-light: #f59e0b;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: linear-gradient(135deg, #1a1a1a 0%, #2a2a2a 100%);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  font-weight: 400;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 2rem 1rem;
}

/* Format Selector - Hidden */
.format-selector {
  display: none;
}

/* Device Frame Container */
.device-frame {
  width: 100%;
  max-width: 100%;
  margin: 0 auto;
  background: var(--bg-color);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

/* Desktop Format (default) */
.device-frame.format-desktop {
  max-width: 100%;
  border: none;
  box-shadow: none;
}

/* Tablet Format */
.device-frame.format-tablet {
  max-width: 768px;
  border: 24px solid #2a2a2a;
  border-top-width: 32px;
  border-bottom-width: 32px;
  border-radius: 24px;
  box-shadow: 
    0 0 0 2px #1a1a1a,
    0 20px 60px rgba(0, 0, 0, 0.6),
    inset 0 0 0 1px rgba(255, 255, 255, 0.1);
  background: var(--bg-color);
  position: relative;
  margin-top: 1rem;
  margin-bottom: 1rem;
}

.device-frame.format-tablet::before {
  content: '';
  position: absolute;
  top: -32px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 8px;
  background: #2a2a2a;
  border-radius: 0 0 8px 8px;
  z-index: 1;
}

.device-frame.format-tablet::after {
  content: '';
  position: absolute;
  top: -32px;
  left: 50%;
  transform: translateX(-50%);
  width: 50px;
  height: 5px;
  background: #1a1a1a;
  border-radius: 0 0 5px 5px;
  z-index: 2;
}

/* Mobile Format */
.device-frame.format-mobile {
  max-width: 375px;
  border: 20px solid #2a2a2a;
  border-top-width: 50px;
  border-bottom-width: 50px;
  border-radius: 32px;
  box-shadow: 
    0 0 0 2px #1a1a1a,
    0 20px 60px rgba(0, 0, 0, 0.6),
    inset 0 0 0 1px rgba(255, 255, 255, 0.1);
  background: var(--bg-color);
  position: relative;
  margin-top: 1rem;
  margin-bottom: 1rem;
}

.device-frame.format-mobile::before {
  content: '';
  position: absolute;
  top: -50px;
  left: 50%;
  transform: translateX(-50%);
  width: 140px;
  height: 30px;
  background: #2a2a2a;
  border-radius: 0 0 20px 20px;
  z-index: 1;
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.3);
}

.device-frame.format-mobile::after {
  content: '';
  position: absolute;
  top: -50px;
  left: 50%;
  transform: translateX(-50%);
  width: 70px;
  height: 8px;
  background: #1a1a1a;
  border-radius: 0 0 8px 8px;
  z-index: 2;
}


/* ============================================
   Navigation
   ============================================ */

nav {
  position: sticky;
  top: 0;
  background-color: var(--card-bg);
  border-bottom: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
  padding: 1rem 2rem;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  transition: var(--transition);
  letter-spacing: 0.5px;
}

.logo-circle {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background-color: var(--primary-color);
  border: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-sm);
  display: inline-block;
  transition: var(--transition);
  flex-shrink: 0;
}

.logo-text {
  display: inline-block;
}

.logo:hover {
  transform: translate(-1px, -1px);
  color: var(--primary-color);
}

.logo:hover .logo-circle {
  transform: scale(1.05);
  box-shadow: var(--shadow-md);
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--ink);
  text-decoration: none;
  font-weight: 600;
  position: relative;
  transition: var(--transition);
  padding: 0.5rem 1rem;
  border: var(--border-medium) solid transparent;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--primary-color);
  transition: width 0.2s ease;
}

.nav-links a:hover {
  color: var(--ink);
  background-color: var(--surface-off);
  border-color: var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-links a.active {
  color: var(--ink);
  background-color: var(--surface-off);
  border-color: var(--primary-color);
  box-shadow: 1px 1px 0 0 var(--ink);
}

.nav-links a.active::after {
  width: 100%;
}

/* Mobile Menu Toggle Button */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  z-index: 1001;
}

.mobile-menu-toggle span {
  width: 24px;
  height: 3px;
  background: var(--ink);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.mobile-menu-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(8px, 8px);
}

.mobile-menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -7px);
}

/* Mobile Menu Overlay */
.mobile-menu-overlay {
  display: none;
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 9999;
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

.mobile-menu-overlay.active {
  display: block;
  opacity: 1;
  pointer-events: all;
}

.mobile-menu {
  position: absolute;
  top: 0;
  right: -100%;
  width: 280px;
  max-width: 85%;
  height: 100%;
  background: var(--card-bg);
  box-shadow: -4px 0 12px rgba(0, 0, 0, 0.15);
  transition: right 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 10000;
  overflow-y: auto;
}

.mobile-menu-overlay.active .mobile-menu {
  right: 0;
}

/* Ensure device frame contains the menu */
.device-frame {
  position: relative;
  overflow: hidden;
}

.mobile-menu-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem;
  border-bottom: var(--border-thick) solid var(--ink);
}

.mobile-menu-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: 0.5px;
}

.mobile-menu-close {
  width: 36px;
  height: 36px;
  background: none;
  border: var(--border-thick) solid var(--ink);
  border-radius: 0;
  font-size: 1.5rem;
  color: var(--ink);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  line-height: 1;
}

.mobile-menu-close:hover {
  background: var(--surface-off);
  transform: translate(-1px, -1px);
  box-shadow: var(--shadow-sm);
}

.mobile-nav-links {
  list-style: none;
  padding: 1rem 0;
}

.mobile-nav-links li {
  border-bottom: 1px solid var(--divider);
}

.mobile-nav-links a {
  display: block;
  padding: 1rem 1.5rem;
  color: var(--ink);
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
}

.mobile-nav-links a:hover {
  background: var(--surface-off);
  color: var(--primary-color);
}

.mobile-nav-links a.active {
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary-color);
  border-left: 3px solid var(--primary-color);
}

/* Show mobile menu in tablet format */
.device-frame.format-tablet .nav-links {
  display: none;
}

.device-frame.format-tablet .mobile-menu-toggle {
  display: flex;
}

.device-frame.format-desktop .mobile-menu-toggle {
  display: none;
}

.device-frame.format-desktop .mobile-menu-overlay {
  display: none !important;
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  background: var(--hero-gradient);
  color: white;
  padding: 4rem 2rem;
  text-align: center;
  border-bottom: var(--border-thick) solid var(--ink);
  box-shadow: 0 4px 0 0 var(--ink);
}

.hero.hero-small {
  padding: 2rem 2rem;
}

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

.hero-icon {
  font-size: 3rem;
  margin-bottom: 1rem;
  display: inline-block;
  animation: fadeInUp 0.6s ease;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 1rem;
  animation: fadeInUp 0.6s ease;
  text-shadow: 2px 2px 0 var(--ink);
  letter-spacing: -0.5px;
}

.hero.hero-small h1 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.hero p {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  opacity: 0.95;
  animation: fadeInUp 0.6s ease 0.2s both;
}

.hero.hero-small p {
  font-size: 1rem;
  margin-bottom: 1rem;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.6s ease 0.4s both;
}

.btn {
  padding: 0.875rem 2rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9375rem;
  border: var(--border-thick) solid var(--ink);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  display: inline-block;
  letter-spacing: 0.3px;
}

.btn-primary {
  background-color: var(--primary-color);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  transform: translate(-1px, -1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: var(--card-bg);
  color: var(--primary-color);
  border: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--surface-off);
  transform: translate(-1px, -1px);
  box-shadow: var(--shadow-md);
  color: var(--primary-color);
}

/* ============================================
   Main Content
   ============================================ */

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 3rem 2rem;
}

.content-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin-bottom: 3rem;
}

.card {
  background-color: var(--card-bg);
  border-radius: var(--radius);
  padding: 2rem;
  border: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

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

.card h2 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.card p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.card ul {
  list-style: none;
  margin-top: 1rem;
}

.card li {
  padding: 0.5rem 0;
  color: var(--text-secondary);
  position: relative;
  padding-left: 1.5rem;
}

.card li::before {
  content: '';
  position: absolute;
  left: 0;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1rem;
}

.tag {
  background-color: var(--card-bg);
  color: var(--ink);
  padding: 0.375rem 0.875rem;
  border-radius: 0;
  font-size: 0.875rem;
  font-weight: 600;
  border: var(--border-medium) solid var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
  letter-spacing: 0.2px;
}

/* Progress Card */
.progress-bar-container {
  background-color: var(--card-bg);
  border-radius: var(--radius-sm);
  height: 14px;
  margin: 1.5rem 0;
  overflow: visible;
  border: var(--border-thick) solid var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
}

.progress-bar {
  background: var(--primary-color);
  height: 100%;
  border-radius: 0;
  width: 0;
  animation: progressFill 1.5s ease forwards;
  border-right: var(--border-thick) solid var(--ink);
}

@keyframes progressFill {
  from {
    width: 0;
  }
}

.module-list {
  list-style: none;
  margin-top: 1.5rem;
}

.module-item {
  display: flex;
  align-items: center;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--divider);
}

.module-item:last-child {
  border-bottom: none;
}

.module-check {
  width: 26px;
  height: 26px;
  border-radius: 0;
  background-color: var(--card-bg);
  color: var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 1rem;
  font-size: 0.875rem;
  flex-shrink: 0;
  border: var(--border-thick) solid var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
  font-weight: 700;
  position: relative;
}

.module-check::before {
  content: '○';
}

.module-item.completed .module-check {
  background-color: var(--success-color);
  color: white;
}

.module-item.completed .module-check::before {
  content: '✓';
}

.module-name {
  flex: 1;
  color: var(--text-primary);
  font-weight: 500;
}

/* ============================================
   KPI Section
   ============================================ */

.kpi-section {
  margin-top: 3rem;
}

.kpi-section h2 {
  font-size: 2rem;
  margin-bottom: 2rem;
  text-align: center;
}

.kpi-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.kpi-card {
  background-color: var(--card-bg);
  border-radius: var(--radius);
  padding: 2rem;
  border: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  position: relative;
  overflow: visible;
}

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

.kpi-card.updating::before {
  transform: scaleX(1);
}

.kpi-card:hover {
  transform: translate(-4px, -4px);
  box-shadow: var(--shadow-lg);
}

.kpi-label {
  font-size: 0.875rem;
  color: var(--ink);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 0.5rem;
  font-weight: 800;
}

.kpi-value {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--primary-color);
  min-height: 3rem;
  display: flex;
  align-items: center;
  letter-spacing: -0.5px;
}

.kpi-value.updating {
  animation: fadeSlide 0.5s ease;
}

/* ============================================
   Animations
   ============================================ */

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

@keyframes fadeSlide {
  0% {
    opacity: 0;
    transform: translateY(-10px);
  }
  50% {
    opacity: 0.5;
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.7;
  }
}

/* ============================================
   Course Taking Interface (HTML/CSS)
   ============================================ */

.hero-course {
  background: var(--hero-gradient);
}

.course-layout {
  display: grid;
  grid-template-columns: 1fr 350px;
  gap: 2rem;
  margin-bottom: 3rem;
}

.course-main {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.video-container {
  width: 100%;
  border-radius: var(--radius);
  overflow: hidden;
  border: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-md);
  background-color: #000;
}

.video-placeholder {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%; /* 16:9 aspect ratio */
  background: linear-gradient(135deg, #1e293b 0%, #334155 100%);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: white;
  cursor: pointer;
  transition: var(--transition);
}

.video-placeholder:hover {
  opacity: 0.9;
}

.play-button {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 70px;
  height: 70px;
  border-radius: 0;
  background-color: var(--primary-color);
  color: white;
  border: var(--border-thick) solid var(--ink);
  box-shadow: 2px 2px 0 0 var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  transition: var(--transition);
  z-index: 2;
}

.video-placeholder:hover .play-button {
  transform: translate(-50%, -50%) translate(-1px, -1px);
  box-shadow: 3px 3px 0 0 var(--ink);
}

.video-placeholder p {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  font-size: 1.125rem;
  font-weight: 500;
  z-index: 1;
}

.lesson-content {
  margin-top: 0;
}

.lesson-meta {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.lesson-text {
  line-height: 1.8;
}

.lesson-text h3 {
  margin-top: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.lesson-text code {
  background-color: var(--bg-color);
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  font-family: 'Courier New', monospace;
  font-size: 0.9em;
  color: var(--primary-color);
}

.lesson-navigation {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

.course-sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.lesson-list {
  list-style: none;
  margin-top: 1rem;
}

.lesson-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem;
  border-radius: var(--radius-sm);
  margin-bottom: 0.5rem;
  cursor: pointer;
  transition: var(--transition);
  border: var(--border-medium) solid transparent;
}

.lesson-item:hover {
  background-color: var(--surface-off);
  border-color: var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
  transform: translate(-1px, -1px);
}

.lesson-item.active {
  background-color: var(--card-bg);
  border: var(--border-thick) solid var(--primary-color);
  box-shadow: 2px 2px 0 0 var(--ink);
}


.lesson-item.completed .lesson-number {
  background-color: var(--success-color);
  color: white;
  border-color: var(--ink);
}

.lesson-item.active .lesson-number {
  background-color: var(--primary-color);
  color: white;
  border-color: var(--ink);
}

.lesson-number {
  width: 32px;
  height: 32px;
  border-radius: 0;
  background-color: var(--card-bg);
  border: var(--border-thick) solid var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.875rem;
  flex-shrink: 0;
  color: var(--ink);
}

.lesson-title {
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.lesson-duration {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* ============================================
   Exam Interface (AR/VR)
   ============================================ */

.hero-exam {
  background: var(--hero-gradient);
}

.exam-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 2rem;
  margin-bottom: 2rem;
  padding: 1.5rem;
  background-color: var(--card-bg);
  border-radius: var(--radius);
  border: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-md);
}

.exam-timer {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.timer-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 0.5rem;
}

.timer-value {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--primary-color);
  font-variant-numeric: tabular-nums;
  text-shadow: 1px 1px 0 var(--ink);
}

.exam-progress {
  flex: 1;
  max-width: 400px;
}

.exam-progress > span {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-primary);
}

.exam-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 2rem;
  margin-bottom: 3rem;
}

.exam-main {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.question-card {
  margin-top: 0;
}

.question-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: var(--border-medium) solid var(--ink);
}

.question-number {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.question-points {
  background-color: var(--accent-amber);
  padding: 0.375rem 0.875rem;
  border-radius: 0;
  font-size: 0.875rem;
  font-weight: 700;
  color: white;
  border: var(--border-medium) solid var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
  text-transform: uppercase;
}

.question-text {
  font-size: 1.5rem;
  margin-bottom: 2rem;
  line-height: 1.6;
  color: var(--text-primary);
}

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

.answer-option {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  padding: 1.25rem;
  border: var(--border-thick) solid var(--ink);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  background-color: var(--card-bg);
  box-shadow: var(--shadow-sm);
}

.answer-option:hover {
  border-color: var(--ink);
  background-color: var(--surface-off);
  transform: translate(-1px, -1px);
  box-shadow: var(--shadow-sm);
}

/* All pages use same hover states */
body[data-topic="html-css"] .answer-option:hover,
body[data-topic="ar-vr"] .answer-option:hover {
  background-color: var(--surface-off);
}

.answer-option input[type="radio"] {
  margin-top: 0.25rem;
  cursor: pointer;
}

.answer-option input[type="radio"]:checked + .answer-label {
  background-color: var(--primary-color);
  color: white;
  border-color: var(--ink);
}

.answer-label {
  width: 32px;
  height: 32px;
  border-radius: 0;
  background-color: var(--card-bg);
  border: var(--border-thick) solid var(--ink);
  box-shadow: 1px 1px 0 0 var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  flex-shrink: 0;
  transition: var(--transition);
  color: var(--ink);
}

.answer-text {
  flex: 1;
  line-height: 1.6;
  color: var(--text-primary);
}

.exam-navigation {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 2rem;
  border-top: var(--border-medium) solid var(--ink);
}

.exam-sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.question-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0.5rem;
  margin-top: 1rem;
}

.question-btn {
  aspect-ratio: 1;
  border: var(--border-thick) solid var(--ink);
  border-radius: var(--radius-sm);
  background-color: var(--card-bg);
  font-weight: 800;
  cursor: pointer;
  transition: var(--transition);
  color: var(--ink);
  box-shadow: var(--shadow-sm);
}

.question-btn:hover {
  border-color: var(--ink);
  background-color: var(--surface-off);
  transform: translate(-1px, -1px);
  box-shadow: var(--shadow-sm);
}

.question-btn.active {
  background-color: var(--primary-color);
  color: white;
  border-color: var(--ink);
  box-shadow: var(--shadow-md);
}

.question-btn.completed {
  background-color: var(--success-color);
  color: white;
  border-color: var(--ink);
  box-shadow: var(--shadow-md);
}

.question-legend {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.legend-color {
  width: 20px;
  height: 20px;
  border-radius: 4px;
  border: 2px solid var(--border-color);
  background-color: var(--card-bg);
}

.legend-color.completed {
  background-color: var(--success-color);
  border-color: var(--success-color);
}

.legend-color.active {
  background-color: var(--primary-color);
  border-color: var(--primary-color);
}

.exam-info {
  margin-top: 1rem;
}

.exam-info p {
  margin-bottom: 0.75rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.exam-info strong {
  color: var(--text-primary);
}

/* ============================================
   Footer
   ============================================ */

footer {
  background-color: var(--card-bg);
  border-top: var(--border-thick) solid var(--ink);
  padding: 2rem;
  text-align: center;
  color: var(--ink);
  margin-top: 4rem;
  font-weight: 500;
  box-shadow: 0 -2px 0 0 var(--ink);
}

footer a {
  text-decoration: none;
  color: var(--ink);
  transition: var(--transition);
}

footer a:hover {
  color: var(--primary-color);
}

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

@media (max-width: 968px) {
  .content-grid {
    grid-template-columns: 1fr;
  }

  .course-layout,
  .exam-layout {
    grid-template-columns: 1fr;
  }

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

  .hero h1 {
    font-size: 2.5rem;
  }

  .exam-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .exam-progress {
    max-width: 100%;
    width: 100%;
  }
}

@media (max-width: 640px) {
  nav {
    padding: 1rem;
  }

  .nav-container {
    flex-direction: column;
    gap: 1rem;
  }

  .nav-links {
    gap: 1rem;
    flex-wrap: wrap;
    justify-content: center;
  }

  .hero {
    padding: 3rem 1.5rem;
  }

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

  .hero p {
    font-size: 1.125rem;
  }

  .container {
    padding: 2rem 1rem;
  }

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

  .kpi-value {
    font-size: 1.75rem;
  }

  .card {
    padding: 1.5rem;
  }

  .course-sidebar,
  .exam-sidebar {
    order: -1;
  }

  .question-grid {
    grid-template-columns: repeat(5, 1fr);
  }
}

/* ============================================
   Unique Design Variations per Page
   ============================================ */

/* Digital Twins - Professional/Minimalist Design (Adaptable-aligned) */
body.design-industrial {
  background-color: #ffffff;
}

body.design-industrial .card {
  border: 1px solid var(--border-color);
  box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.05), 0 1px 2px 0 rgba(0, 0, 0, 0.03);
  background: #ffffff;
  transition: all 0.2s ease;
}

body.design-industrial .card:hover {
  border-color: var(--primary-color);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(14, 165, 233, 0.1), 0 2px 4px rgba(0, 0, 0, 0.05);
}

body.design-industrial .hero {
  background: var(--hero-gradient);
  position: relative;
  overflow: hidden;
}

body.design-industrial .hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.08) 50%, transparent 100%);
  pointer-events: none;
}

body.design-industrial .btn {
  border: 1px solid;
  font-weight: 600;
  letter-spacing: 0.3px;
  font-size: 0.9375rem;
}

body.design-industrial .btn-primary {
  background-color: white;
  border-color: white;
  color: var(--primary-color);
}

body.design-industrial .btn-primary:hover {
  background-color: rgba(255, 255, 255, 0.95);
  border-color: rgba(255, 255, 255, 0.95);
  color: var(--primary-hover);
}

body.design-industrial .btn-secondary {
  background-color: transparent;
  border-color: white;
  color: white;
}

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

body.design-industrial .tag {
  border: 1px solid var(--border-color);
  background-color: #f8fafc;
  font-weight: 500;
  color: var(--text-secondary);
}

body.design-industrial .progress-bar-container {
  border: 1px solid var(--border-color);
  background-color: #f8fafc;
}

body.design-industrial nav {
  border-bottom: var(--border-thick) solid var(--ink);
  background: var(--surface);
  box-shadow: 0 4px 0 0 var(--ink);
}

/* HTML/CSS - Neo-Brutal-Lite Design */
body.design-creative {
  background: var(--surface-off);
}

body.design-creative .card {
  background: var(--surface);
  border: var(--border-thick) solid var(--ink);
  box-shadow: var(--shadow-md);
  transition: all 0.2s ease;
}

body.design-creative .card:hover {
  transform: translate(-4px, -4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--ink);
}

body.design-creative .hero {
  position: relative;
  overflow: hidden;
}

body.design-creative .hero::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 30% 50%, rgba(255,255,255,0.1) 0%, transparent 50%);
  pointer-events: none;
}

body.design-creative .btn {
  border: 1px solid;
  font-weight: 600;
}

body.design-creative .btn-primary {
  background-color: white;
  border-color: white;
  color: var(--primary-color);
}

body.design-creative .btn-primary:hover {
  background-color: rgba(255, 255, 255, 0.95);
  border-color: rgba(255, 255, 255, 0.95);
  color: var(--primary-hover);
}

body.design-creative .tag {
  background: var(--surface-off);
  border: var(--border-medium) solid var(--ink);
  color: var(--ink);
  font-weight: 600;
  box-shadow: 1px 1px 0 0 var(--ink);
}

body.design-creative .video-container {
  border: 1px solid var(--border-color);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

body.design-creative .play-button {
  background: var(--primary-color);
  box-shadow: 0 4px 12px rgba(20, 184, 166, 0.3);
}

body.design-creative .lesson-item {
  border-left: 3px solid transparent;
  transition: all 0.2s ease;
}

body.design-creative .lesson-item:hover {
  border-left-color: var(--primary-color);
  background-color: #f0fdfa;
}

/* AR/VR - Neo-Brutal-Lite Design */
body.design-futuristic {
  background: var(--surface);
  min-height: 100vh;
}

body.design-futuristic .container {
  position: relative;
}

body.design-futuristic .card {
  background: #ffffff;
  border: 1px solid rgba(56, 189, 248, 0.2);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05), 0 1px 2px rgba(0, 0, 0, 0.03);
  color: var(--text-primary);
  border-radius: var(--radius);
  transition: all 0.2s ease;
}

body.design-futuristic .card h2,
body.design-futuristic .card h3 {
  color: var(--text-primary);
}

body.design-futuristic .card p,
body.design-futuristic .card span:not(.timer-value):not(.timer-label),
body.design-futuristic .card strong {
  color: var(--text-primary);
}

body.design-futuristic .module-name,
body.design-futuristic .lesson-title,
body.design-futuristic .lesson-duration {
  color: var(--text-primary);
}

body.design-futuristic .card:hover {
  background: #ffffff;
  border-color: var(--primary-color);
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(56, 189, 248, 0.12), 0 2px 4px rgba(0, 0, 0, 0.05);
}

body.design-futuristic .exam-header {
  background: #ffffff;
  border: 1px solid rgba(56, 189, 248, 0.2);
  color: var(--text-primary);
  border-radius: var(--radius);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

body.design-futuristic .exam-header span {
  color: var(--text-primary);
}

body.design-futuristic .timer-value {
  color: var(--primary-color);
}

body.design-futuristic .timer-label {
  color: var(--text-secondary);
}

body.design-futuristic .answer-option {
  background: #ffffff;
  border: 1px solid rgba(56, 189, 248, 0.2);
  color: var(--text-primary);
  border-radius: var(--radius-sm);
}

body.design-futuristic .answer-option:hover {
  background: #f0f9ff;
  border-color: var(--primary-color);
}

body.design-futuristic .answer-text {
  color: var(--text-primary);
}

body.design-futuristic .question-text {
  color: var(--text-primary);
}

body.design-futuristic .btn {
  background: #ffffff;
  border: 1px solid rgba(56, 189, 248, 0.3);
  color: var(--text-primary);
  border-radius: var(--radius-sm);
  font-weight: 600;
}

body.design-futuristic .btn:hover {
  background: #f0f9ff;
  border-color: var(--primary-color);
  color: var(--primary-color);
}

body.design-futuristic .btn-primary {
  background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
  border: none;
  color: white;
}

body.design-futuristic .btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-hover), var(--primary-color));
  box-shadow: 0 8px 24px rgba(56, 189, 248, 0.4);
  color: white;
}

body.design-futuristic .question-btn {
  background: #ffffff;
  border: 1px solid rgba(56, 189, 248, 0.2);
  color: var(--text-primary);
  border-radius: var(--radius-sm);
}

body.design-futuristic .question-btn:hover {
  background: #f0f9ff;
  border-color: var(--primary-color);
}

body.design-futuristic .question-btn.active {
  background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
  border-color: transparent;
  color: white;
}

body.design-futuristic .progress-bar-container {
  background: #e0f2fe;
  border: 1px solid rgba(56, 189, 248, 0.2);
  border-radius: var(--radius-sm);
}

body.design-futuristic nav {
  background: #ffffff;
  border-bottom: 1px solid rgba(56, 189, 248, 0.1);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

body.design-futuristic .logo,
body.design-futuristic .nav-links a {
  color: var(--text-primary);
}

body.design-futuristic .nav-links a:hover {
  color: var(--primary-color);
}

body.design-futuristic .nav-links a::after {
  background-color: var(--primary-color);
}

body.design-futuristic footer {
  background: #ffffff;
  border-top: 1px solid rgba(56, 189, 248, 0.1);
  color: var(--text-secondary);
}