/* === GameWorld — Neon Scholar Theme === */
:root {
  --bg: #0A0E17;
  --surface: #0F131D;
  --surface-high: #1A1F2C;
  --surface-highest: #202633;
  --primary: #72DCFF;
  --accent: #00FDEE;
  --tertiary: #AC89FF;
  --on-surface: #EBEDFB;
  --on-surface-variant: #A7ABB7;
  --error: #FF716C;
  --gradient-start: #00D2FF;
  --gradient-end: #00FDEE;
  --outline: #444852;
  --font-heading: 'Space Grotesk', 'Inter', sans-serif;
  --font-body: 'Manrope', 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --max-width: 1100px;
  --radius: 0.375rem;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--on-surface);
  font-family: var(--font-body);
  font-size: 1.05rem;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--primary); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent); }

code { font-family: var(--font-mono); background: var(--surface-highest); padding: 0.15em 0.4em; border-radius: 3px; font-size: 0.9em; }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* === Sections === */
.section { padding: 80px 0; }
.section-alt { background: var(--surface); }

h2 {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 2px solid transparent;
  border-image: linear-gradient(90deg, var(--gradient-start), var(--gradient-end), transparent) 1;
}

h3 {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 500;
  margin-bottom: 12px;
  color: var(--on-surface);
}

h4 {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 500;
  margin-bottom: 8px;
}

p { margin-bottom: 16px; color: var(--on-surface-variant); }
p:last-child { margin-bottom: 0; }

ul, ol { margin-bottom: 16px; padding-left: 24px; color: var(--on-surface-variant); }
li { margin-bottom: 8px; }

/* === Hero === */
.hero {
  position: relative;
  min-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: url('./assets/bg_hero.png') center/cover no-repeat;
  z-index: 0;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(10,14,23,0.92) 0%, rgba(10,14,23,0.7) 100%);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 900px;
  padding: 60px 24px;
}

.hero h1 {
  font-family: var(--font-heading);
  font-size: 3.6rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  color: var(--on-surface);
}

.gradient-text {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--on-surface-variant);
  margin-bottom: 24px;
  line-height: 1.6;
}

.venue-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--tertiary);
  border: 1px solid rgba(172,137,255,0.3);
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 20px;
  letter-spacing: 0.05em;
}

.hero-authors {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin-bottom: 12px;
}

.author-chip {
  background: var(--surface-high);
  padding: 5px 14px;
  border-radius: 20px;
  font-size: 0.9rem;
  color: var(--on-surface-variant);
}

.hero-affiliations {
  font-size: 0.85rem;
  color: var(--on-surface-variant);
  margin-bottom: 28px;
  opacity: 0.8;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* === Buttons === */
.btn {
  display: inline-block;
  padding: 10px 24px;
  border-radius: var(--radius);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.3s;
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: #004C5E;
}
.btn-primary:hover { box-shadow: 0 0 30px rgba(0,210,255,0.3); color: #004C5E; }

.btn-secondary {
  background: transparent;
  color: var(--primary);
  border: 1px solid rgba(114,220,255,0.3);
}
.btn-secondary:hover { border-color: var(--primary); }

/* === Metric Badges === */
.metric-badges {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 24px;
  justify-content: center;
}

.metric-badge {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
  background: rgba(114,220,255,0.08);
  border: 1px solid rgba(114,220,255,0.2);
  padding: 6px 16px;
  border-radius: 20px;
}

/* === Cards === */
.card-grid { display: grid; gap: 24px; }
.three-col { grid-template-columns: repeat(3, 1fr); }
.two-col { grid-template-columns: repeat(2, 1fr); }

.card {
  background: var(--surface-high);
  border-radius: var(--radius);
  padding: 24px 28px;
  border: 1px solid rgba(68,72,82,0.15);
  transition: border-color 0.3s;
}
.card:hover { border-color: rgba(114,220,255,0.4); }

.glow-card {
  border-top: 2px solid transparent;
  border-image: linear-gradient(90deg, var(--gradient-start), var(--gradient-end)) 1;
  border-image-slice: 1;
}

.card-number {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
  opacity: 0.3;
  margin-bottom: 8px;
}

/* === Interface Cards === */
.cua-card { border-left: 3px solid var(--primary); }
.gen-card { border-left: 3px solid var(--accent); }

/* === Figures === */
.figure-block {
  background: var(--surface-highest);
  border-radius: var(--radius);
  padding: 16px;
  margin: 24px 0;
  border: 1px solid rgba(68,72,82,0.15);
}
.figure-block.compact { padding: 12px; }

.figure-block img { border-radius: 3px; margin: 0 auto; }

.figure-block figcaption {
  font-size: 0.85rem;
  color: var(--on-surface-variant);
  margin-top: 12px;
  line-height: 1.5;
}

/* === Principles Grid === */
.principles-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 24px;
}

.principle-item {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  background: var(--surface-high);
  padding: 16px;
  border-radius: var(--radius);
}

.principle-num {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--primary);
  flex-shrink: 0;
  width: 28px;
}

.principle-item p { margin: 0; font-size: 0.95rem; }

/* === Game Grid === */
.game-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
  margin-bottom: 32px;
}

.game-card {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid rgba(68,72,82,0.15);
  transition: border-color 0.3s, box-shadow 0.3s;
}
.game-card:hover {
  border-color: rgba(114,220,255,0.4);
  box-shadow: 0 0 20px rgba(114,220,255,0.1);
}

.game-label {
  position: absolute;
  top: 8px;
  left: 8px;
}

.genre-badge {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 3px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.genre-badge.arcade { background: rgba(172,137,255,0.8); color: #fff; }
.genre-badge.platformer { background: rgba(0,253,238,0.8); color: #004C5E; }
.genre-badge.puzzle { background: rgba(114,220,255,0.8); color: #004C5E; }
.genre-badge.runner { background: rgba(255,113,108,0.8); color: #fff; }
.genre-badge.simulation { background: rgba(0,210,255,0.8); color: #004C5E; }

/* === Two Column Layout === */
.two-col-layout {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 32px;
  align-items: start;
}

/* === Rank Cards === */
.rank-card { text-align: center; position: relative; }

.rank-badge {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 4px 12px;
  border-radius: 3px;
  margin-bottom: 12px;
  display: inline-block;
}

.rank-1 .rank-badge { background: linear-gradient(135deg, #FFD700, #FFA500); color: #1a1a2e; }
.rank-2 .rank-badge { background: linear-gradient(135deg, #C0C0C0, #A0A0A0); color: #1a1a2e; }
.rank-3 .rank-badge { background: linear-gradient(135deg, #CD7F32, #B8690F); color: #fff; }

.score {
  font-family: var(--font-mono);
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--accent);
  margin: 8px 0;
}

/* === Callout Box === */
.callout-box {
  background: var(--surface-high);
  border-left: 3px solid var(--accent);
  padding: 20px 24px;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 24px 0;
}

/* === Level Cards === */
.level-cards {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.level-card {
  background: var(--surface-high);
  padding: 16px;
  border-radius: var(--radius);
  text-align: center;
  border-top: 3px solid;
}

.level-1 { border-color: #22c55e; }
.level-2 { border-color: #84cc16; }
.level-3 { border-color: #eab308; }
.level-4 { border-color: #f97316; }
.level-5 { border-color: #ef4444; }

.level-num {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 700;
  display: block;
  margin-bottom: 8px;
}

.level-1 .level-num { color: #22c55e; }
.level-2 .level-num { color: #84cc16; }
.level-3 .level-num { color: #eab308; }
.level-4 .level-num { color: #f97316; }
.level-5 .level-num { color: #ef4444; }

.level-card p { font-size: 0.85rem; margin: 0; }

/* === Challenge Blocks === */
.challenge-block {
  background: var(--surface-high);
  padding: 24px 28px;
  border-radius: var(--radius);
  margin-bottom: 20px;
  border: 1px solid rgba(68,72,82,0.15);
}

.challenge-block h3 { color: var(--primary); }

/* === Case Studies === */
.case-study { margin-bottom: 48px; }
.case-study:last-child { margin-bottom: 0; }

/* === Related Work === */
.related-block { margin-bottom: 24px; }
.related-block h3 { color: var(--primary); font-size: 1.15rem; }

/* === References === */
details { margin-bottom: 16px; }

details summary {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 500;
  cursor: pointer;
  padding: 12px 0;
  color: var(--on-surface);
  list-style: none;
}
details summary::before { content: '\25B6 '; font-size: 0.8em; color: var(--primary); }
details[open] summary::before { content: '\25BC '; }

.references-list {
  font-size: 0.8rem;
  color: var(--on-surface-variant);
  line-height: 1.6;
  padding-left: 20px;
}
.references-list li { margin-bottom: 4px; }

/* === Flecto Explanation UI === */
.flecto-note,
.flecto-callout,
.flecto-card,
.flecto-panel {
  margin: 16px 0;
  padding: 16px 20px;
  border-radius: var(--radius);
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--on-surface-variant);
}

.flecto-note::before,
.flecto-callout::before,
.flecto-card::before,
.flecto-panel::before {
  content: '\1F916 AI explanation';
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  color: #60a5fa;
  letter-spacing: 0.06em;
  display: block;
  margin-bottom: 0.5em;
}

.flecto-note {
  background: rgba(114,220,255,0.05);
  border-left: 3px solid var(--primary);
  font-size: 0.9rem;
}

.flecto-callout {
  background: rgba(172,137,255,0.08);
  border: 1px solid rgba(172,137,255,0.15);
}

.flecto-card {
  background: var(--surface-highest);
  border: 1px solid var(--outline);
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.flecto-panel {
  background: var(--surface-high);
  border: 1px solid rgba(114,220,255,0.15);
  padding: 20px 24px;
}

.flecto-note h4, .flecto-callout h4, .flecto-card h4, .flecto-panel h4 {
  color: var(--on-surface);
  margin-bottom: 8px;
}

/* === Reveal Animation === */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* === Responsive === */
@media (max-width: 900px) {
  .three-col { grid-template-columns: 1fr; }
  .two-col { grid-template-columns: 1fr; }
  .two-col-layout { grid-template-columns: 1fr; }
  .principles-grid { grid-template-columns: 1fr; }
  .game-grid { grid-template-columns: repeat(3, 1fr); }
  .level-cards { grid-template-columns: repeat(3, 1fr); }
  .hero h1 { font-size: 2.4rem; }
  .hero-subtitle { font-size: 1.05rem; }
}

@media (max-width: 600px) {
  .game-grid { grid-template-columns: repeat(2, 1fr); }
  .level-cards { grid-template-columns: 1fr; }
  .hero h1 { font-size: 2rem; }
  .section { padding: 48px 0; }
  h2 { font-size: 1.6rem; }
}