/* ==========================================================================
   Formation & Quiz IA / Prompt Engineering - Modern Premium Theme
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800&family=Plus+Jakarta+Sans:wght@400;500;600;700&family=Fira+Code:wght@400;500&display=swap');

:root {
  --font-main: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-heading: 'Outfit', sans-serif;
  --font-code: 'Fira Code', monospace;

  /* Color Palette - Dark Mode Default */
  --bg-primary: #0b0f19;
  --bg-secondary: #111827;
  --bg-card: rgba(17, 24, 39, 0.7);
  --bg-card-hover: rgba(31, 41, 55, 0.8);
  --bg-glass: rgba(255, 255, 255, 0.03);

  --border-color: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(99, 102, 241, 0.3);

  --text-primary: #f9fafb;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;

  --accent-primary: #6366f1;
  --accent-primary-hover: #4f46e5;
  --accent-secondary: #8b5cf6;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;
  --accent-rose: #f43f5e;

  --gradient-brand: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #d946ef 100%);
  --gradient-card: linear-gradient(145deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.01) 100%);
  --gradient-glow: radial-gradient(circle at 50% -20%, rgba(99, 102, 241, 0.15), transparent 70%);

  --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
  --shadow-md: 0 10px 30px -10px rgba(0,0,0,0.5);
  --shadow-glow: 0 0 25px rgba(99, 102, 241, 0.25);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;

  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.85);
  --bg-card-hover: rgba(241, 245, 249, 1);
  --bg-glass: rgba(0, 0, 0, 0.02);

  --border-color: rgba(0, 0, 0, 0.08);
  --border-glow: rgba(99, 102, 241, 0.4);

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;

  --shadow-md: 0 10px 30px -10px rgba(0,0,0,0.08);
  --shadow-glow: 0 0 25px rgba(99, 102, 241, 0.15);
}

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

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

body {
  font-family: var(--font-main);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  background-image: var(--gradient-glow);
  background-attachment: fixed;
  transition: var(--transition);
}

/* Layout */
.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 15, 25, 0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 2rem;
}

[data-theme="light"] .app-header {
  background: rgba(248, 250, 252, 0.85);
}

.header-container {
  max-width: 1300px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

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

.brand-icon {
  width: 42px;
  height: 42px;
  background: var(--gradient-brand);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  box-shadow: var(--shadow-glow);
}

.brand-text h1 {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.brand-text p {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* Navigation Tabs */
.nav-tabs {
  display: flex;
  background: var(--bg-glass);
  padding: 4px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  gap: 4px;
}

.tab-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 0.6rem 1.25rem;
  font-family: var(--font-main);
  font-weight: 600;
  font-size: 0.9rem;
  border-radius: 10px;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.tab-btn:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.tab-btn.active {
  background: var(--accent-primary);
  color: #fff;
  box-shadow: var(--shadow-glow);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.theme-toggle, .btn-icon {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  transition: var(--transition);
}

.theme-toggle:hover, .btn-icon:hover {
  border-color: var(--accent-primary);
  transform: translateY(-2px);
}

/* Main Container */
.main-content {
  max-width: 1300px;
  margin: 2rem auto;
  padding: 0 1.5rem;
}

.tab-pane {
  display: none;
  animation: fadeIn 0.3s ease;
}

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

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Hero Section */
.hero-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  margin-bottom: 2rem;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.hero-card::before {
  content: '';
  position: absolute;
  top: 0; right: 0; width: 300px; height: 300px;
  background: var(--gradient-brand);
  filter: blur(100px);
  opacity: 0.15;
  pointer-events: none;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(99, 102, 241, 0.15);
  border: 1px solid var(--border-glow);
  color: var(--accent-primary);
  padding: 0.4rem 0.9rem;
  border-radius: 30px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.hero-title {
  font-family: var(--font-heading);
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 1rem;
}

.hero-subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 800px;
  margin-bottom: 1.5rem;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  margin-top: 1.5rem;
}

.stat-item {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
}

.stat-value {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent-primary);
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* Grid Layout for Course Reader */
.course-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 1.75rem;
  align-items: start;
}

/* Sidebar Navigation */
.sidebar-nav {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  position: sticky;
  top: 90px;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
}

.search-box {
  margin-bottom: 1.25rem;
}

.search-input {
  width: 100%;
  padding: 0.7rem 1rem;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.875rem;
  outline: none;
  transition: var(--transition);
}

.search-input:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.toc-group {
  margin-bottom: 1.25rem;
}

.toc-title {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  padding-left: 0.5rem;
}

.toc-list {
  list-style: none;
}

.toc-link {
  display: block;
  padding: 0.5rem 0.75rem;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.toc-link:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.toc-link.active {
  color: var(--accent-primary);
  background: rgba(99, 102, 241, 0.1);
  font-weight: 600;
}

/* Course Article Viewer */
.course-article {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-md);
}

.course-article h2 {
  font-family: var(--font-heading);
  font-size: 1.8rem;
  margin: 2rem 0 1rem 0;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-primary);
}

.course-article h2:first-child {
  margin-top: 0;
}

.course-article h3 {
  font-family: var(--font-heading);
  font-size: 1.3rem;
  margin: 1.5rem 0 0.75rem 0;
  color: var(--accent-primary);
}

.course-article h4 {
  font-size: 1.1rem;
  margin: 1.25rem 0 0.5rem 0;
}

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

.course-article ul, .course-article ol {
  margin-bottom: 1.25rem;
  padding-left: 1.5rem;
  color: var(--text-secondary);
}

.course-article li {
  margin-bottom: 0.4rem;
}

/* Styled Table */
.table-container {
  overflow-x: auto;
  margin: 1.5rem 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.styled-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.9rem;
}

.styled-table th {
  background: rgba(99, 102, 241, 0.15);
  color: var(--text-primary);
  padding: 0.85rem 1rem;
  font-family: var(--font-heading);
  font-weight: 600;
}

.styled-table td {
  padding: 0.85rem 1rem;
  border-top: 1px solid var(--border-color);
  color: var(--text-secondary);
}

.styled-table tr:hover {
  background: rgba(255, 255, 255, 0.02);
}

/* Prompt Card Box */
.prompt-card {
  background: rgba(17, 24, 39, 0.9);
  border: 1px solid var(--border-glow);
  border-left: 4px solid var(--accent-primary);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  margin: 1.5rem 0;
  position: relative;
}

[data-theme="light"] .prompt-card {
  background: #f1f5f9;
}

.prompt-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.75rem;
}

.prompt-badge {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--accent-primary);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.btn-copy {
  background: rgba(99, 102, 241, 0.15);
  border: 1px solid var(--border-glow);
  color: var(--accent-primary);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.btn-copy:hover {
  background: var(--accent-primary);
  color: #fff;
}

.prompt-text {
  font-family: var(--font-code);
  font-size: 0.9rem;
  line-height: 1.6;
  color: #e2e8f0;
  white-space: pre-wrap;
}

[data-theme="light"] .prompt-text {
  color: #1e293b;
}

/* Alert Boxes */
.alert-box {
  padding: 1.25rem;
  border-radius: var(--radius-md);
  margin: 1.25rem 0;
  display: flex;
  gap: 1rem;
  border: 1px solid transparent;
}

.alert-box.tip {
  background: rgba(16, 185, 129, 0.08);
  border-color: rgba(16, 185, 129, 0.25);
  color: var(--accent-emerald);
}

.alert-box.important {
  background: rgba(99, 102, 241, 0.08);
  border-color: rgba(99, 102, 241, 0.25);
  color: var(--accent-primary);
}

.alert-icon {
  font-size: 1.4rem;
  flex-shrink: 0;
}

.alert-content p {
  color: var(--text-primary);
  font-size: 0.95rem;
}

/* ==========================================================================
   QUIZ INTERACTIVE ENGINE
   ========================================================================== */
.quiz-container {
  max-width: 900px;
  margin: 0 auto;
}

.quiz-card {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-md);
}

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

.quiz-step {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.quiz-score-badge {
  background: rgba(16, 185, 129, 0.15);
  color: var(--accent-emerald);
  border: 1px solid rgba(16, 185, 129, 0.3);
  padding: 0.35rem 0.85rem;
  border-radius: 20px;
  font-weight: 700;
  font-size: 0.85rem;
}

.progress-bar-bg {
  width: 100%;
  height: 8px;
  background: var(--bg-glass);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 2rem;
  border: 1px solid var(--border-color);
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: var(--gradient-brand);
  border-radius: 4px;
  transition: width 0.3s ease;
}

.question-text {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}

.options-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-bottom: 2rem;
}

.option-item {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 1rem;
}

.option-item:hover {
  border-color: var(--accent-primary);
  background: rgba(99, 102, 241, 0.05);
}

.option-radio {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 2px solid var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: var(--transition);
}

.option-item.selected .option-radio {
  border-color: var(--accent-primary);
  background: var(--accent-primary);
}

.option-item.selected .option-radio::after {
  content: '';
  width: 8px;
  height: 8px;
  background: #fff;
  border-radius: 50%;
}

.option-label {
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 500;
}

/* Feedback Box */
.feedback-box {
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  margin-bottom: 1.75rem;
  display: none;
  animation: fadeIn 0.3s ease;
}

.feedback-box.correct {
  display: block;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: var(--accent-emerald);
}

.feedback-box.incorrect {
  display: block;
  background: rgba(244, 63, 94, 0.1);
  border: 1px solid rgba(244, 63, 94, 0.3);
  color: var(--accent-rose);
}

.feedback-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 0.4rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.feedback-desc {
  font-size: 0.9rem;
  color: var(--text-primary);
}

/* Quiz Controls */
.quiz-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.btn-primary {
  background: var(--gradient-brand);
  color: #fff;
  border: none;
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  opacity: 0.95;
}

.btn-secondary {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.btn-secondary:hover {
  border-color: var(--text-muted);
}

/* Quiz Result Modal / View */
.quiz-result-card {
  text-align: center;
  padding: 3rem 2rem;
  display: none;
}

.quiz-result-card.active {
  display: block;
  animation: fadeIn 0.4s ease;
}

.result-badge-icon {
  font-size: 4rem;
  margin-bottom: 1rem;
}

.result-score {
  font-family: var(--font-heading);
  font-size: 3.5rem;
  font-weight: 800;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 0.5rem;
}

.result-title {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.result-desc {
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 2rem auto;
}

/* Prompt Generator Builder */
.builder-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

@media (max-width: 900px) {
  .course-layout, .builder-grid {
    grid-template-columns: 1fr;
  }
  .sidebar-nav {
    position: relative;
    top: 0;
  }
  .nav-tabs {
    flex-wrap: wrap;
  }
}

.form-group {
  margin-bottom: 1.25rem;
}

.form-label {
  display: block;
  font-weight: 600;
  font-size: 0.875rem;
  margin-bottom: 0.4rem;
  color: var(--text-primary);
}

.form-input, .form-textarea, .form-select {
  width: 100%;
  padding: 0.75rem 1rem;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-main);
  font-size: 0.9rem;
  outline: none;
  transition: var(--transition);
}

.form-textarea {
  resize: vertical;
  min-height: 80px;
}

.form-input:focus, .form-textarea:focus, .form-select:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 1000;
}

.toast {
  background: rgba(17, 24, 39, 0.95);
  border: 1px solid var(--accent-emerald);
  color: #fff;
  padding: 0.85rem 1.4rem;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  animation: slideUp 0.3s ease;
}

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