/* ========================================
   2026 CALT 學習需求分析與個人學習 — 教學網站
   全域樣式表 (Design System & Global Styles)
   ======================================== */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Noto+Sans+TC:wght@300;400;500;700&family=Noto+Serif+TC:wght@700&display=swap');

/* --- CSS Custom Properties (Design Tokens) --- */
:root {
  /* Colors - Warm Neutral Base */
  --bg-primary: #F5F3EF;
  --bg-secondary: #EDEAE4;
  --bg-card: #FFFFFF;
  --bg-card-hover: #FAFAF8;
  --bg-dark: #2D2A26;

  /* Text */
  --text-primary: #2D2A26;
  --text-secondary: #6B6560;
  --text-light: #9B9590;
  --text-inverse: #F5F3EF;

  /* Accent Colors */
  --accent-purple: #4A3F8A;
  --accent-purple-light: #6B5FB5;
  --accent-purple-bg: rgba(74, 63, 138, 0.08);
  --accent-gold: #C4A44A;
  --accent-gold-light: #D4B85A;
  --accent-gold-bg: rgba(196, 164, 74, 0.1);

  /* Semantic Colors */
  --color-success: #3D8B5E;
  --color-success-bg: rgba(61, 139, 94, 0.1);
  --color-error: #C74B3C;
  --color-error-bg: rgba(199, 75, 60, 0.1);
  --color-warning: #D4873E;
  --color-warning-bg: rgba(212, 135, 62, 0.1);
  --color-info: #5B8DB8;
  --color-info-bg: rgba(91, 141, 184, 0.1);

  /* KSAE Quadrant Colors */
  --k-color: #5B8DB8;
  --k-bg: rgba(91, 141, 184, 0.12);
  --s-color: #D4873E;
  --s-bg: rgba(212, 135, 62, 0.12);
  --a-color: #8B5DAD;
  --a-bg: rgba(139, 93, 173, 0.12);
  --e-color: #4A9B6F;
  --e-bg: rgba(74, 155, 111, 0.12);

  /* Typography */
  --font-primary: 'Noto Sans TC', 'Inter', sans-serif;
  --font-serif: 'Noto Serif TC', serif;
  --font-mono: 'Fira Code', 'Consolas', monospace;

  /* Font Sizes */
  --fs-xs: 0.75rem;
  --fs-sm: 0.875rem;
  --fs-base: 1rem;
  --fs-md: 1.125rem;
  --fs-lg: 1.25rem;
  --fs-xl: 1.5rem;
  --fs-2xl: 1.875rem;
  --fs-3xl: 2.25rem;
  --fs-4xl: 3rem;

  /* Spacing */
  --sp-1: 0.25rem;
  --sp-2: 0.5rem;
  --sp-3: 0.75rem;
  --sp-4: 1rem;
  --sp-5: 1.25rem;
  --sp-6: 1.5rem;
  --sp-8: 2rem;
  --sp-10: 2.5rem;
  --sp-12: 3rem;
  --sp-16: 4rem;
  --sp-20: 5rem;

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

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(45, 42, 38, 0.06);
  --shadow-md: 0 4px 12px rgba(45, 42, 38, 0.08);
  --shadow-lg: 0 8px 30px rgba(45, 42, 38, 0.1);
  --shadow-xl: 0 16px 50px rgba(45, 42, 38, 0.12);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
  --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

  /* Layout */
  --max-width: 1200px;
  --header-height: 64px;
}

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

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

body {
  font-family: var(--font-primary);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent-purple); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: var(--accent-purple-light); }
button { cursor: pointer; font-family: inherit; }
ul, ol { list-style: none; }

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
}

h1 { font-size: var(--fs-3xl); font-family: var(--font-serif); }
h2 { font-size: var(--fs-2xl); }
h3 { font-size: var(--fs-xl); }
h4 { font-size: var(--fs-lg); }
h5 { font-size: var(--fs-md); }

p { margin-bottom: var(--sp-4); color: var(--text-secondary); }

.text-accent { color: var(--accent-purple); }
.text-gold { color: var(--accent-gold); }
.text-success { color: var(--color-success); }
.text-error { color: var(--color-error); }

/* --- Layout Utilities --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--sp-6);
}

.section {
  padding: var(--sp-16) 0;
}

.section-sm {
  padding: var(--sp-10) 0;
}

.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--sp-2); }
.gap-3 { gap: var(--sp-3); }
.gap-4 { gap: var(--sp-4); }
.gap-6 { gap: var(--sp-6); }
.gap-8 { gap: var(--sp-8); }

.grid { display: grid; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

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

/* --- Header / Navigation --- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(245, 243, 239, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(45, 42, 38, 0.06);
  height: var(--header-height);
  transition: box-shadow var(--transition-base);
}

.site-header.scrolled {
  box-shadow: var(--shadow-md);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--sp-6);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  font-weight: 700;
  font-size: var(--fs-md);
  color: var(--text-primary);
  text-decoration: none;
}

.nav-logo .logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--accent-purple), var(--accent-gold));
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--fs-lg);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
}

.nav-links a {
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--radius-sm);
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent-purple);
  background: var(--accent-purple-bg);
}

.nav-hamburger {
  display: none;
  background: none;
  border: none;
  padding: var(--sp-2);
  color: var(--text-primary);
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: currentColor;
  margin: 5px 0;
  transition: all var(--transition-base);
  border-radius: 2px;
}

/* Mobile Nav */
.mobile-nav {
  display: none;
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(245, 243, 239, 0.98);
  backdrop-filter: blur(20px);
  z-index: 999;
  padding: var(--sp-6);
  overflow-y: auto;
}

.mobile-nav.open { display: block; }

.mobile-nav a {
  display: block;
  padding: var(--sp-4) var(--sp-4);
  font-size: var(--fs-md);
  color: var(--text-secondary);
  border-bottom: 1px solid rgba(45, 42, 38, 0.06);
  transition: all var(--transition-fast);
}

.mobile-nav a:hover,
.mobile-nav a.active {
  color: var(--accent-purple);
  background: var(--accent-purple-bg);
  border-radius: var(--radius-sm);
}

/* Main content offset for fixed header */
main {
  padding-top: var(--header-height);
}

/* --- Hero Section --- */
.hero {
  padding: var(--sp-20) 0 var(--sp-16);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -20%;
  width: 140%;
  height: 200%;
  background: radial-gradient(ellipse at 30% 20%, var(--accent-purple-bg) 0%, transparent 50%),
              radial-gradient(ellipse at 70% 60%, var(--accent-gold-bg) 0%, transparent 50%);
  z-index: 0;
  pointer-events: none;
}

.hero > * { position: relative; z-index: 1; }

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
  background: var(--accent-purple-bg);
  border: 1px solid rgba(74, 63, 138, 0.15);
  border-radius: var(--radius-full);
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--accent-purple);
  margin-bottom: var(--sp-6);
}

.hero h1 {
  font-size: var(--fs-4xl);
  margin-bottom: var(--sp-4);
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: var(--fs-lg);
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto var(--sp-8);
  line-height: 1.8;
}

/* --- Cards --- */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(45, 42, 38, 0.06);
  padding: var(--sp-8);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
  border-color: rgba(74, 63, 138, 0.12);
}

.card-sm {
  padding: var(--sp-6);
}

.card-flat {
  box-shadow: none;
  border: 1px solid rgba(45, 42, 38, 0.08);
}

.card-flat:hover {
  box-shadow: var(--shadow-md);
}

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

.card-gold {
  border-left: 4px solid var(--accent-gold);
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--fs-xl);
  margin-bottom: var(--sp-4);
}

.card-icon.purple { background: var(--accent-purple-bg); color: var(--accent-purple); }
.card-icon.gold { background: var(--accent-gold-bg); color: var(--accent-gold); }
.card-icon.blue { background: var(--k-bg); color: var(--k-color); }
.card-icon.orange { background: var(--s-bg); color: var(--s-color); }
.card-icon.violet { background: var(--a-bg); color: var(--a-color); }
.card-icon.green { background: var(--e-bg); color: var(--e-color); }

.card h3, .card h4 {
  margin-bottom: var(--sp-3);
}

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

/* --- KSAE Tag --- */
.ksae-tag {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-1);
  padding: var(--sp-1) var(--sp-3);
  border-radius: var(--radius-full);
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: 0.5px;
}

.ksae-tag.k { background: var(--k-bg); color: var(--k-color); }
.ksae-tag.s { background: var(--s-bg); color: var(--s-color); }
.ksae-tag.a { background: var(--a-bg); color: var(--a-color); }
.ksae-tag.e { background: var(--e-bg); color: var(--e-color); }

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-6);
  border-radius: var(--radius-md);
  font-size: var(--fs-base);
  font-weight: 600;
  border: none;
  transition: all var(--transition-base);
  cursor: pointer;
  text-decoration: none;
  line-height: 1.5;
}

.btn-primary {
  background: var(--accent-purple);
  color: white;
}
.btn-primary:hover {
  background: var(--accent-purple-light);
  color: white;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid rgba(45, 42, 38, 0.1);
}
.btn-secondary:hover {
  background: var(--bg-card);
  box-shadow: var(--shadow-sm);
}

.btn-outline {
  background: transparent;
  color: var(--accent-purple);
  border: 2px solid var(--accent-purple);
}
.btn-outline:hover {
  background: var(--accent-purple);
  color: white;
}

.btn-gold {
  background: linear-gradient(135deg, var(--accent-gold), var(--accent-gold-light));
  color: white;
}
.btn-gold:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-sm {
  padding: var(--sp-2) var(--sp-4);
  font-size: var(--fs-sm);
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: var(--sp-4) var(--sp-8);
  font-size: var(--fs-md);
  border-radius: var(--radius-md);
}

.btn-block {
  width: 100%;
}

/* KSAE Buttons */
.btn-k { background: var(--k-color); color: white; }
.btn-k:hover { background: #4A7CA8; color: white; box-shadow: 0 4px 16px rgba(91,141,184,0.3); }
.btn-s { background: var(--s-color); color: white; }
.btn-s:hover { background: #C4772E; color: white; box-shadow: 0 4px 16px rgba(212,135,62,0.3); }
.btn-a { background: var(--a-color); color: white; }
.btn-a:hover { background: #7B4D9D; color: white; box-shadow: 0 4px 16px rgba(139,93,173,0.3); }
.btn-e { background: var(--e-color); color: white; }
.btn-e:hover { background: #3A8B5F; color: white; box-shadow: 0 4px 16px rgba(74,155,111,0.3); }

/* --- Timeline --- */
.timeline {
  position: relative;
  padding-left: var(--sp-10);
}

.timeline::before {
  content: '';
  position: absolute;
  left: 16px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent-purple), var(--accent-gold));
  border-radius: 2px;
}

.timeline-item {
  position: relative;
  margin-bottom: var(--sp-8);
  animation: fadeSlideUp 0.5s ease forwards;
  opacity: 0;
}

.timeline-item:nth-child(1) { animation-delay: 0.1s; }
.timeline-item:nth-child(2) { animation-delay: 0.2s; }
.timeline-item:nth-child(3) { animation-delay: 0.3s; }
.timeline-item:nth-child(4) { animation-delay: 0.4s; }
.timeline-item:nth-child(5) { animation-delay: 0.5s; }
.timeline-item:nth-child(6) { animation-delay: 0.6s; }

.timeline-dot {
  position: absolute;
  left: -34px;
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent-purple);
  border: 3px solid var(--bg-primary);
  box-shadow: 0 0 0 2px var(--accent-purple);
}

.timeline-time {
  font-size: var(--fs-xs);
  font-weight: 600;
  color: var(--accent-purple);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: var(--sp-2);
}

/* --- Flip Card --- */
.flip-card {
  perspective: 1000px;
  height: 220px;
  cursor: pointer;
}

.flip-card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform var(--transition-slow);
  transform-style: preserve-3d;
}

.flip-card.flipped .flip-card-inner {
  transform: rotateY(180deg);
}

.flip-card-front,
.flip-card-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: var(--radius-lg);
  padding: var(--sp-6);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  border: 1px solid rgba(45, 42, 38, 0.06);
}

.flip-card-front {
  background: var(--bg-card);
}

.flip-card-back {
  background: var(--bg-card);
  transform: rotateY(180deg);
  font-size: var(--fs-sm);
  line-height: 1.6;
  overflow-y: auto;
}

.flip-card-front .flip-icon {
  font-size: 2.5rem;
  margin-bottom: var(--sp-3);
}

.flip-hint {
  font-size: var(--fs-xs);
  color: var(--text-light);
  margin-top: var(--sp-3);
}

/* --- Accordion --- */
.accordion-item {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  border: 1px solid rgba(45, 42, 38, 0.06);
  margin-bottom: var(--sp-3);
  overflow: hidden;
  transition: box-shadow var(--transition-base);
}

.accordion-item:hover {
  box-shadow: var(--shadow-sm);
}

.accordion-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-4) var(--sp-6);
  background: none;
  border: none;
  width: 100%;
  font-family: inherit;
  font-size: var(--fs-base);
  font-weight: 600;
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.accordion-header:hover {
  background: var(--bg-secondary);
}

.accordion-icon {
  transition: transform var(--transition-base);
  font-size: var(--fs-sm);
  color: var(--text-light);
}

.accordion-item.open .accordion-icon {
  transform: rotate(180deg);
}

.accordion-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}

.accordion-item.open .accordion-content {
  max-height: 800px;
}

.accordion-body {
  padding: 0 var(--sp-6) var(--sp-6);
  color: var(--text-secondary);
  line-height: 1.8;
}

/* --- Quiz / Interactive --- */
.quiz-container {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  padding: var(--sp-10);
  border: 1px solid rgba(45, 42, 38, 0.06);
  box-shadow: var(--shadow-md);
}

.quiz-progress {
  display: flex;
  gap: var(--sp-2);
  margin-bottom: var(--sp-8);
}

.quiz-progress-dot {
  flex: 1;
  height: 4px;
  border-radius: 2px;
  background: var(--bg-secondary);
  transition: background var(--transition-base);
}

.quiz-progress-dot.active {
  background: var(--accent-purple);
}

.quiz-progress-dot.done {
  background: var(--color-success);
}

.quiz-question {
  font-size: var(--fs-lg);
  font-weight: 600;
  margin-bottom: var(--sp-6);
  line-height: 1.7;
  color: var(--text-primary);
}

.quiz-scenario {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: var(--sp-6);
  margin-bottom: var(--sp-6);
  border-left: 4px solid var(--accent-gold);
  font-size: var(--fs-base);
  line-height: 1.8;
  color: var(--text-primary);
}

.quiz-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-4);
  margin-bottom: var(--sp-6);
}

.quiz-option {
  padding: var(--sp-4) var(--sp-6);
  border-radius: var(--radius-md);
  border: 2px solid rgba(45, 42, 38, 0.1);
  background: var(--bg-card);
  cursor: pointer;
  transition: all var(--transition-base);
  font-size: var(--fs-base);
  font-weight: 500;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  min-height: 60px;
}

.quiz-option:hover {
  border-color: var(--accent-purple);
  background: var(--accent-purple-bg);
  transform: translateY(-1px);
}

.quiz-option.selected {
  border-color: var(--accent-purple);
  background: var(--accent-purple-bg);
  color: var(--accent-purple);
}

.quiz-option.correct {
  border-color: var(--color-success);
  background: var(--color-success-bg);
  color: var(--color-success);
}

.quiz-option.incorrect {
  border-color: var(--color-error);
  background: var(--color-error-bg);
  color: var(--color-error);
}

.quiz-explanation {
  padding: var(--sp-6);
  border-radius: var(--radius-md);
  margin-top: var(--sp-4);
  animation: fadeSlideUp 0.3s ease;
}

.quiz-explanation.correct {
  background: var(--color-success-bg);
  border: 1px solid rgba(61, 139, 94, 0.2);
}

.quiz-explanation.incorrect {
  background: var(--color-error-bg);
  border: 1px solid rgba(199, 75, 60, 0.2);
}

/* --- Blind Box / Mystery Card --- */
.blindbox-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-6);
}

.blindbox {
  width: 280px;
  height: 180px;
  perspective: 1000px;
  cursor: pointer;
}

.blindbox-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.blindbox.revealed .blindbox-inner {
  transform: rotateY(180deg);
}

.blindbox-front,
.blindbox-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  text-align: center;
  padding: var(--sp-4);
}

.blindbox-front {
  background: linear-gradient(135deg, var(--accent-purple), var(--accent-gold));
  color: white;
  font-size: 3rem;
  box-shadow: var(--shadow-lg);
}

.blindbox-front span {
  font-size: var(--fs-sm);
  margin-top: var(--sp-2);
  opacity: 0.8;
}

.blindbox-back {
  transform: rotateY(180deg);
  background: var(--bg-card);
  border: 2px solid var(--accent-gold);
  font-size: var(--fs-sm);
  line-height: 1.6;
  color: var(--text-primary);
}

.blindbox-card-content {
  max-width: 600px;
  width: 100%;
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  padding: var(--sp-8);
  border: 1px solid rgba(45, 42, 38, 0.08);
  box-shadow: var(--shadow-md);
  min-height: 200px;
}

/* --- Drag & Drop --- */
.drag-zone {
  min-height: 120px;
  border: 2px dashed rgba(45, 42, 38, 0.15);
  border-radius: var(--radius-md);
  padding: var(--sp-4);
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  align-content: flex-start;
  transition: all var(--transition-fast);
}

.drag-zone.dragover {
  border-color: var(--accent-purple);
  background: var(--accent-purple-bg);
}

.drag-item {
  padding: var(--sp-2) var(--sp-4);
  background: var(--bg-card);
  border: 1px solid rgba(45, 42, 38, 0.1);
  border-radius: var(--radius-sm);
  cursor: grab;
  font-size: var(--fs-sm);
  transition: all var(--transition-fast);
  user-select: none;
}

.drag-item:active { cursor: grabbing; }
.drag-item:hover {
  box-shadow: var(--shadow-sm);
  border-color: var(--accent-purple);
}

.drag-item.correct {
  background: var(--color-success-bg);
  border-color: var(--color-success);
  color: var(--color-success);
}

.drag-item.incorrect {
  background: var(--color-error-bg);
  border-color: var(--color-error);
  color: var(--color-error);
}

/* --- Forms --- */
.form-group {
  margin-bottom: var(--sp-6);
}

.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--sp-2);
  font-size: var(--fs-sm);
  color: var(--text-primary);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: var(--sp-3) var(--sp-4);
  border: 1px solid rgba(45, 42, 38, 0.15);
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: var(--fs-base);
  color: var(--text-primary);
  background: var(--bg-card);
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--accent-purple);
  box-shadow: 0 0 0 3px var(--accent-purple-bg);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
  line-height: 1.7;
}

/* Checkbox Style */
.checkbox-row {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-3) 0;
}

.checkbox-custom {
  width: 20px;
  height: 20px;
  border: 2px solid rgba(45, 42, 38, 0.2);
  border-radius: 4px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.checkbox-custom.checked {
  background: var(--color-success);
  border-color: var(--color-success);
  color: white;
}

/* --- Slider --- */
.range-slider-group {
  margin-bottom: var(--sp-6);
}

.range-slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  background: var(--bg-secondary);
  border-radius: 3px;
  outline: none;
  cursor: pointer;
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent-purple);
  border: 3px solid white;
  box-shadow: var(--shadow-md);
  cursor: pointer;
  transition: transform var(--transition-fast);
}

.range-slider::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

.range-value {
  font-size: var(--fs-2xl);
  font-weight: 700;
  color: var(--accent-purple);
  text-align: center;
  margin-bottom: var(--sp-2);
}

/* --- Tables --- */
.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid rgba(45, 42, 38, 0.08);
}

table {
  width: 100%;
  border-collapse: collapse;
}

th, td {
  padding: var(--sp-3) var(--sp-4);
  text-align: left;
  border-bottom: 1px solid rgba(45, 42, 38, 0.06);
  font-size: var(--fs-sm);
}

th {
  background: var(--bg-secondary);
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
}

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

tr:hover td {
  background: var(--bg-card-hover);
}

/* Interactive Matrix Cell */
.matrix-cell {
  cursor: pointer;
  text-align: center;
  transition: all var(--transition-fast);
  font-weight: 600;
}

.matrix-cell:hover {
  background: var(--accent-purple-bg);
  color: var(--accent-purple);
}

.matrix-cell.active {
  background: var(--accent-purple);
  color: white;
}

/* --- Blockquote / Quote Card --- */
.quote-card {
  background: linear-gradient(135deg, var(--accent-purple-bg), var(--accent-gold-bg));
  border-radius: var(--radius-lg);
  padding: var(--sp-8);
  border-left: 4px solid var(--accent-gold);
  position: relative;
}

.quote-card::before {
  content: '"';
  font-family: var(--font-serif);
  font-size: 4rem;
  color: var(--accent-gold);
  opacity: 0.3;
  position: absolute;
  top: var(--sp-4);
  left: var(--sp-6);
  line-height: 1;
}

.quote-card p {
  font-size: var(--fs-lg);
  font-weight: 500;
  color: var(--text-primary);
  line-height: 1.8;
  padding-left: var(--sp-8);
}

/* --- Collapsible / Reveal --- */
.reveal-btn {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-6);
  background: var(--bg-secondary);
  border: 1px solid rgba(45, 42, 38, 0.1);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  width: 100%;
  font-family: inherit;
  font-size: var(--fs-base);
}

.reveal-btn:hover {
  background: var(--accent-purple-bg);
  color: var(--accent-purple);
}

.reveal-content {
  display: none;
  animation: fadeSlideUp 0.3s ease;
}

.reveal-content.visible {
  display: block;
}

/* --- Poll / Voting --- */
.poll-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-4);
  margin-bottom: var(--sp-6);
}

.poll-option {
  padding: var(--sp-4);
  border-radius: var(--radius-md);
  border: 2px solid rgba(45, 42, 38, 0.1);
  background: var(--bg-card);
  cursor: pointer;
  transition: all var(--transition-base);
  text-align: center;
  font-weight: 500;
}

.poll-option:hover {
  border-color: var(--accent-purple);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.poll-option.selected {
  border-color: var(--accent-purple);
  background: var(--accent-purple-bg);
}

.poll-bar {
  height: 32px;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  overflow: hidden;
  margin-bottom: var(--sp-2);
}

.poll-bar-fill {
  height: 100%;
  border-radius: var(--radius-sm);
  background: linear-gradient(90deg, var(--accent-purple), var(--accent-purple-light));
  transition: width 0.8s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  align-items: center;
  padding: 0 var(--sp-3);
  color: white;
  font-size: var(--fs-sm);
  font-weight: 600;
  min-width: 40px;
}

/* --- Timer --- */
.timer {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
  background: var(--bg-dark);
  color: var(--text-inverse);
  border-radius: var(--radius-full);
  font-size: var(--fs-md);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

.timer-icon {
  animation: pulse 1s ease infinite;
}

/* --- Score / Progress --- */
.score-display {
  text-align: center;
  padding: var(--sp-8);
}

.score-number {
  font-size: var(--fs-4xl);
  font-weight: 700;
  color: var(--accent-purple);
}

.score-label {
  font-size: var(--fs-sm);
  color: var(--text-light);
  margin-top: var(--sp-1);
}

.progress-ring {
  transform: rotate(-90deg);
}

/* --- Page Header (for sub-pages) --- */
.page-header {
  padding: var(--sp-12) 0 var(--sp-8);
  text-align: center;
  position: relative;
}

.page-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(180deg, var(--accent-purple-bg) 0%, transparent 100%);
  z-index: 0;
}

.page-header > * { position: relative; z-index: 1; }

.page-header .unit-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: var(--accent-purple);
  color: white;
  border-radius: 50%;
  font-size: var(--fs-lg);
  font-weight: 700;
  margin-bottom: var(--sp-4);
}

.page-header h1 {
  font-size: var(--fs-2xl);
  margin-bottom: var(--sp-3);
}

.page-header .page-subtitle {
  color: var(--text-secondary);
  font-size: var(--fs-md);
  max-width: 600px;
  margin: 0 auto;
}

.page-header .time-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
  background: var(--accent-gold-bg);
  border-radius: var(--radius-full);
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--accent-gold);
  margin-top: var(--sp-4);
}

/* --- Prev/Next Navigation --- */
.page-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--sp-4);
  padding: var(--sp-10) 0;
  border-top: 1px solid rgba(45, 42, 38, 0.08);
  margin-top: var(--sp-10);
}

.page-nav a {
  display: flex;
  flex-direction: column;
  gap: var(--sp-1);
  padding: var(--sp-4) var(--sp-6);
  border-radius: var(--radius-md);
  border: 1px solid rgba(45, 42, 38, 0.08);
  background: var(--bg-card);
  transition: all var(--transition-base);
  flex: 1;
  max-width: 300px;
}

.page-nav a:hover {
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}

.page-nav a .nav-direction {
  font-size: var(--fs-xs);
  color: var(--text-light);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.page-nav a .nav-title {
  font-weight: 600;
  color: var(--text-primary);
}

.page-nav .next { text-align: right; margin-left: auto; }

/* --- Footer --- */
.site-footer {
  background: var(--bg-dark);
  color: var(--text-inverse);
  padding: var(--sp-10) 0 var(--sp-6);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--sp-8);
  margin-bottom: var(--sp-8);
}

.footer-brand h3 {
  color: var(--text-inverse);
  font-size: var(--fs-md);
  margin-bottom: var(--sp-2);
}

.footer-brand p {
  color: rgba(245, 243, 239, 0.6);
  font-size: var(--fs-sm);
}

.footer-links h4 {
  color: var(--text-inverse);
  font-size: var(--fs-sm);
  margin-bottom: var(--sp-3);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.footer-links a {
  display: block;
  color: rgba(245, 243, 239, 0.6);
  font-size: var(--fs-sm);
  padding: var(--sp-1) 0;
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  border-top: 1px solid rgba(245, 243, 239, 0.1);
  padding-top: var(--sp-6);
  text-align: center;
  font-size: var(--fs-xs);
  color: rgba(245, 243, 239, 0.4);
}

/* --- Radar Chart Container --- */
.radar-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-6);
}

.radar-canvas-wrapper {
  width: 360px;
  height: 360px;
  position: relative;
}

/* --- Typewriter Effect --- */
.typewriter {
  overflow: hidden;
  border-right: 2px solid var(--accent-gold);
  white-space: nowrap;
  animation: typing 3s steps(40, end), blinkCursor 0.6s step-end infinite;
}

/* --- Animations --- */
@keyframes fadeSlideUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

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

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

@keyframes typing {
  from { width: 0; }
  to { width: 100%; }
}

@keyframes blinkCursor {
  from, to { border-color: transparent; }
  50% { border-color: var(--accent-gold); }
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-5px); }
  75% { transform: translateX(5px); }
}

@keyframes bounceIn {
  0% { transform: scale(0); opacity: 0; }
  60% { transform: scale(1.15); }
  100% { transform: scale(1); opacity: 1; }
}

.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s ease;
}

.animate-on-scroll.visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- Responsive Design --- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  :root {
    --fs-4xl: 2.25rem;
    --fs-3xl: 1.875rem;
    --fs-2xl: 1.5rem;
  }

  .nav-links { display: none; }
  .nav-hamburger { display: block; }

  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }

  .quiz-options {
    grid-template-columns: 1fr;
  }

  .poll-options {
    grid-template-columns: 1fr;
  }

  .hero { padding: var(--sp-12) 0 var(--sp-8); }

  .page-nav {
    flex-direction: column;
  }

  .page-nav a { max-width: none; }

  .footer-content {
    flex-direction: column;
  }

  .flip-card { height: 260px; }
}

@media (max-width: 480px) {
  :root {
    --fs-4xl: 1.875rem;
    --fs-3xl: 1.5rem;
  }

  .container { padding: 0 var(--sp-4); }
  .card { padding: var(--sp-6); }
  .quiz-container { padding: var(--sp-6); }
}

/* --- Print Styles --- */
@media print {
  .site-header,
  .site-footer,
  .page-nav,
  .nav-hamburger,
  .btn,
  .timer { display: none !important; }

  main { padding-top: 0; }

  body {
    background: white;
    color: black;
    font-size: 12pt;
  }

  .card {
    box-shadow: none;
    border: 1px solid #ccc;
    break-inside: avoid;
  }

  .form-input,
  .form-textarea {
    border: 1px solid #999;
  }
}