:root {
  --bg: #0a0c10;
  --surface: #111318;
  --surface2: #1a1d25;
  --border: #252830;
  --accent: #e8ff47;
  --accent2: #47c8ff;
  --accent3: #ff6b47;
  --text: #e8eaf0;
  --muted: #6b7080;
  --tag-bg: #1e2130;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'DM Sans', sans-serif;
  font-size: 15px;
  line-height: 1.6;
  overflow-x: hidden;
}

/* ── NOISE OVERLAY ── */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.04'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 0;
  opacity: 0.4;
}

/* ── HERO ── */
.hero {
  position: relative;
  padding: 40px 40px 40px;
  text-align: center;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}

.hero-glow {
  position: absolute;
  top: -100px; left: 50%;
  transform: translateX(-50%);
  width: 700px; height: 400px;
  background: radial-gradient(ellipse, rgba(232,255,71,0.08) 0%, transparent 70%);
  pointer-events: none;
}

.hero-eyebrow {
  font-family: 'DM Mono', monospace;
  font-size: 11px;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.1s;
}

.hero h1 {
  font-family: 'Bebas Neue', sans-serif;
  font-size: clamp(52px, 8vw, 96px);
  letter-spacing: 2px;
  line-height: 0.95;
  color: #fff;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.2s;
}

.hero h1 span { color: var(--accent); }

.hero-sub {
  margin-top: 20px;
  color: var(--muted);
  font-size: 15px;
  max-width: 560px;
  margin-left: auto; margin-right: auto;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.35s;
}

.badges {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 28px;
  opacity: 0;
  animation: fadeUp 0.6s ease forwards 0.45s;
}

.badge {
  background: var(--tag-bg);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 5px 14px;
  font-family: 'DM Mono', monospace;
  font-size: 11px;
  color: var(--muted);
}

.badge.accent { border-color: var(--accent); color: var(--accent); }

/* ── STATS BAR ── */
.stats-bar {
  display: flex;
  justify-content: center;
  gap: 0;
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
}

.stat {
  padding: 20px 36px;
  text-align: center;
  border-right: 1px solid var(--border);
  flex-shrink: 0;
}
.stat:last-child { border-right: none; }

.stat-num {
  font-family: 'Bebas Neue', sans-serif;
  font-size: 32px;
  color: var(--accent);
  line-height: 1;
}

.stat-label {
  font-size: 11px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-top: 4px;
}

/* ── LAYOUT ── */
.layout {
  display: flex;
  min-height: calc(100vh - 300px);
  position: relative;
  z-index: 1;
}

/* ── SIDEBAR ── */
.sidebar {
  width: 280px;
  flex-shrink: 0;
  padding: 32px 0;
  border-right: 1px solid var(--border);
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

.sidebar-label {
  font-family: 'DM Mono', monospace;
  font-size: 11px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--muted);
  padding: 0 26px 16px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 26px;
  cursor: pointer;
  color: var(--muted);
  font-size: 16px;
  transition: all 0.15s;
  border-left: 2px solid transparent;
  text-decoration: none;
}

.nav-item:hover, .nav-item.active {
  color: var(--text);
  background: var(--surface2);
  border-left-color: var(--accent);
}

.nav-item .emoji { font-size: 20px; }

/* ── MAIN CONTENT ── */
.main {
  flex: 1;
  padding: 40px 48px;
  max-width: 1200px;
}

/* ── SPORT SECTION ── */
.sport-section {
  margin-bottom: 72px;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.sport-section.visible {
  opacity: 1;
  transform: translateY(0);
}

.section-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 28px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.section-emoji {
  font-size: 36px;
  line-height: 1;
}

.section-title {
  font-family: 'Bebas Neue', sans-serif;
  font-size: 44px;
  letter-spacing: 1px;
  color: #fff;
}

.section-count {
  margin-left: auto;
  font-family: 'DM Mono', monospace;
  font-size: 11px;
  color: var(--muted);
  background: var(--tag-bg);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 12px;
}

/* ── SUBSECTION ── */
.subsection-title {
  font-family: 'DM Mono', monospace;
  font-size: 10px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent2);
  margin-bottom: 12px;
  margin-top: 28px;
}

/* ── PAPER CARD ── */
.papers-list { display: flex; flex-direction: column; gap: 8px; }

.paper-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 18px 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: border-color 0.2s, background 0.2s;
  cursor: default;
}

.paper-card:hover {
  border-color: rgba(232,255,71,0.3);
  background: var(--surface2);
}

.paper-year {
  font-family: 'DM Mono', monospace;
  font-size: 11px;
  color: var(--accent);
  background: rgba(232,255,71,0.08);
  border: 1px solid rgba(232,255,71,0.2);
  padding: 3px 8px;
  border-radius: 4px;
  flex-shrink: 0;
  min-width: 44px;
  text-align: center;
}

.paper-title {
  flex: 1;
  font-size: 16px;
  color: var(--text);
  font-weight: 500;
}

.paper-links { display: flex; gap: 6px; flex-shrink: 0; }

.link-btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 12px;
  border-radius: 4px;
  font-size: 12px;
  font-family: 'DM Mono', monospace;
  text-decoration: none;
  transition: all 0.15s;
  border: 1px solid;
}

.link-btn.paper {
  color: var(--accent2);
  border-color: rgba(71,200,255,0.3);
  background: rgba(71,200,255,0.05);
}
.link-btn.paper:hover {
  background: rgba(71,200,255,0.15);
  border-color: var(--accent2);
}

.link-btn.code {
  color: var(--accent3);
  border-color: rgba(255,107,71,0.3);
  background: rgba(255,107,71,0.05);
}
.link-btn.code:hover {
  background: rgba(255,107,71,0.15);
  border-color: var(--accent3);
}

/* ── DATASET GRID ── */
.dataset-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 10px;
}

.dataset-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px 16px;
  transition: border-color 0.2s, transform 0.2s;
}

.dataset-card:hover {
  border-color: rgba(71,200,255,0.3);
  transform: translateY(-2px);
}

.dataset-name {
  font-weight: 600;
  font-size: 15px;
  color: #fff;
  margin-bottom: 4px;
}

.dataset-name a {
  color: inherit;
  text-decoration: none;
}
.dataset-name a:hover { color: var(--accent2); }

.dataset-year {
  display: inline-block;
  font-family: 'DM Mono', monospace;
  font-size: 10px;
  color: var(--muted);
  margin-bottom: 6px;
}

.dataset-desc {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
}

/* ── CHALLENGE PILL ── */
.challenges-list { display: flex; flex-direction: column; gap: 8px; }

.challenge-item {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 16px;
}

.challenge-dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
}

.challenge-name { font-size: 15px; font-weight: 500; flex: 1; }
.challenge-name a { color: var(--text); text-decoration: none; }
.challenge-name a:hover { color: var(--accent); }

.challenge-year {
  font-family: 'DM Mono', monospace;
  font-size: 11px;
  color: var(--muted);
}

/* ── VENUES ── */
.venues-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 12px;
}

.venue-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 18px 20px;
  transition: border-color 0.2s;
}

.venue-card:hover { border-color: rgba(232,255,71,0.3); }

.venue-name { font-weight: 600; font-size: 16px; margin-bottom: 6px; }
.venue-name a { color: #fff; text-decoration: none; }
.venue-name a:hover { color: var(--accent); }

.venue-year {
  font-family: 'DM Mono', monospace;
  font-size: 11px;
  color: var(--accent);
  margin-bottom: 6px;
}

.venue-desc { font-size: 14px; color: var(--muted); }

/* ── CITATION ── */
.citation-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px 24px;
  font-family: 'DM Mono', monospace;
  font-size: 12px;
  color: var(--muted);
  line-height: 1.8;
  position: relative;
  overflow: hidden;
}

.citation-box::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 3px;
  background: var(--accent);
}

.copy-btn {
  position: absolute;
  top: 12px; right: 12px;
  background: var(--tag-bg);
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 5px 12px;
  border-radius: 4px;
  font-size: 11px;
  cursor: pointer;
  font-family: 'DM Mono', monospace;
  transition: all 0.15s;
}
.copy-btn:hover { color: var(--accent); border-color: var(--accent); }

/* ── FOOTER ── */
footer {
  border-top: 1px solid var(--border);
  padding: 28px 48px;
  text-align: center;
  color: var(--muted);
  font-size: 13px;
}

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

/* ── THEME TOGGLE ── */
.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 1000;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--surface);
  border: 2px solid var(--border);
  color: var(--text);
  font-size: 24px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
}

.theme-toggle:hover {
  border-color: var(--accent);
  transform: rotate(20deg);
}

/* ── LIGHT THEME ── */
[data-theme="light"] {
  --bg: #ffffff;
  --surface: #f8f8f8;
  --surface2: #f0f0f0;
  --border: #d0d0d0;
  --accent: #d4a573;
  --accent2: #0052cc;
  --accent3: #d32f2f;
  --text: #1a1a1a;
  --muted: #555555;
  --tag-bg: #f0f0f0;
}

[data-theme="light"] body::before {
  opacity: 0.05;
}

[data-theme="light"] .hero h1 {
  color: #000000;
}

[data-theme="light"] .hero-eyebrow {
  color: var(--accent);
}

[data-theme="light"] .stat-num {
  color: var(--accent);
}

[data-theme="light"] .badge.accent {
  color: var(--accent);
  border-color: var(--accent);
}

[data-theme="light"] .nav-item:hover,
[data-theme="light"] .nav-item.active {
  border-left-color: var(--accent);
}

[data-theme="light"] .section-title {
  color: #000000;
}

[data-theme="light"] .paper-card {
  background: #ffffff;
  border-color: #d0d0d0;
}

[data-theme="light"] .paper-card:hover {
  border-color: rgba(212, 165, 115, 0.4);
  background: #f8f8f8;
}

[data-theme="light"] .dataset-card {
  background: #ffffff;
  border-color: #d0d0d0;
}

[data-theme="light"] .dataset-card:hover {
  border-color: rgba(0, 82, 204, 0.3);
}

[data-theme="light"] .dataset-name {
  color: #000000;
}

[data-theme="light"] .challenge-item {
  background: #ffffff;
  border-color: #d0d0d0;
}

[data-theme="light"] .venue-card {
  background: #ffffff;
  border-color: #d0d0d0;
}

[data-theme="light"] .venue-card:hover {
  border-color: rgba(212, 165, 115, 0.3);
}

[data-theme="light"] .venue-name {
  color: #000000;
}

[data-theme="light"] .citation-box {
  background: #ffffff;
  border-color: #d0d0d0;
  color: #555555;
}

[data-theme="light"] .copy-btn {
  background: #f0f0f0;
  border-color: #d0d0d0;
  color: #555555;
}

[data-theme="light"] .copy-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

[data-theme="light"] .theme-toggle {
  background: #f0f0f0;
  border-color: #d0d0d0;
  color: #1a1a1a;
}

/* ── ANIMATIONS ── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── SCROLLBAR ── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--muted); }

@media (max-width: 768px) {
  .sidebar { display: none; }
  .main { padding: 24px 20px; }
  .hero { padding: 48px 20px 40px; }
  .stat { padding: 16px 20px; }
  .paper-card { flex-wrap: wrap; }
}