:root {
  --bg: #0a0e17;
  --surface: #111827;
  --card: #1a2332;
  --border: #2a3a4e;
  --red: #ef4444;
  --orange: #f59e0b;
  --yellow: #eab308;
  --green: #22c55e;
  --blue: #3b82f6;
  --purple: #8b5cf6;
  --teal: #14b8a6;
  --pink: #ec4899;
  --text: #e2e8f0;
  --dim: #94a3b8;
  --font: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.6;
  overflow-x: hidden;
}
a { color: var(--teal); text-decoration: none; transition: color 0.2s; }
a:hover { color: #5eead4; }
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10,14,23,0.85); backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  padding: 12px 24px;
  padding-top: calc(12px + env(safe-area-inset-top));
  display: flex; align-items: center; gap: 16px;
  overflow-x: auto;
  scrollbar-width: none;
}
.nav::-webkit-scrollbar { display: none; }
.nav .brand {
  color: var(--teal); font-weight: 700; font-size: 14px;
  margin-right: 24px; white-space: nowrap; flex-shrink: 0;
  display: flex; align-items: center; gap: 8px;
}
.nav .brand .acc { display: inline-block; width: 8px; height: 8px; border-radius: 50%; background: var(--red); animation: pulse 2s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: 0.3; } }
.hero {
  padding: calc(120px + env(safe-area-inset-top)) 24px 64px; text-align: center;
  background: radial-gradient(circle at top right, rgba(239,68,68,0.05), transparent),
              radial-gradient(circle at bottom left, rgba(20,184,166,0.03), transparent),
              linear-gradient(180deg, #0f172a 0%, #0a0e17 100%);
  border-bottom: 1px solid var(--border);
}
.hero h1 { font-size: clamp(28px,4vw,44px); font-weight: 800; margin-bottom: 12px; }
.hero .subtitle { font-size: 17px; color: var(--dim); max-width: 650px; margin: 0 auto 20px; }
.container { max-width: 1000px; margin: 0 auto; padding: 40px 24px; }
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: 16px;
  padding: 28px; margin-bottom: 20px;
  transition: border-color 0.2s, transform 0.2s;
}
.card:hover { border-color: var(--teal); transform: translateY(-2px); }
.card h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 8px; }
.card .num-badge { display: inline-flex; align-items: center; justify-content: center; width: 28px; height: 28px; border-radius: 8px; font-size: 12px; font-weight: 700; flex-shrink: 0; }
.card .hdr { display: flex; align-items: center; gap: 12px; }
.card .meta-line { font-size: 13px; color: var(--dim); margin-bottom: 12px; }
.card p { color: var(--dim); margin-bottom: 12px; line-height: 1.7; font-size: 14px; }
.card .thesis { font-size: 14px; font-weight: 500; color: var(--text); padding: 10px 14px; background: rgba(255,255,255,0.03); border-radius: 8px; margin-bottom: 12px; border-left: 3px solid var(--teal); }
.card .tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; }
.card .tag { padding: 4px 10px; border-radius: 6px; font-size: 12px; font-weight: 500; background: rgba(255,255,255,0.05); color: var(--dim); }
.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 20px; }
.badge { display: inline-block; padding: 6px 16px; border-radius: 20px; font-size: 13px; font-weight: 600; }
.section { margin-bottom: 48px; }
.section h2 { font-size: 22px; font-weight: 700; margin-bottom: 20px; }
.footer { text-align: center; padding: 40px 24px; color: var(--dim); font-size: 13px; border-top: 1px solid var(--border); }
@media (max-width: 640px) {
  .container { padding: 24px 16px; }
  .card { padding: 20px; }
  .grid-2 { grid-template-columns: 1fr; }
  .hero { padding: calc(100px + env(safe-area-inset-top)) 16px 40px; }
}