:root {
  --bg: #0a0a0a;
  --panel: #111111;
  --border: #1a1a1a;
  --text: #f5f5f5;
  --muted: #9ca3af;
  --yellow: #facc15;
}
* { box-sizing: border-box; }
body {
  margin: 0; font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial;
  background: var(--bg); color: var(--text);
}
.nav {
  display: flex; justify-content: space-between; align-items: center;
  padding: 20px 32px; border-bottom: 1px solid var(--border); position: sticky; top: 0; background: rgba(10,10,10,0.9); backdrop-filter: blur(6px);
}
.logo { font-weight: 700; letter-spacing: .5px; }
.links a { color: var(--muted); text-decoration: none; margin-left: 18px; font-size: 14px; }
.links a:hover { color: white; }
.hero { padding: 80px 32px 40px; max-width: 900px; margin: 0 auto; }
.badge { display: inline-block; background: #111; border: 1px solid var(--border); padding: 6px 10px; border-radius: 999px; font-size: 12px; color: var(--muted); }
.hero h1 { font-size: 56px; margin: 20px 0 8px; }
.subhead { font-size: 20px; color: var(--muted); max-width: 700px; }
.cta { margin-top: 24px; display: flex; gap: 12px; }
button { border: none; padding: 12px 18px; border-radius: 10px; font-weight: 600; cursor: pointer; }
.primary { background: var(--yellow); color: #111; }
.ghost { background: #111; color: white; border: 1px solid var(--border); }
.meta { margin-top: 18px; color: var(--muted); font-size: 14px; }
.section { padding: 48px 32px; max-width: 900px; margin: 0 auto; }
.section h2 { font-size: 28px; margin-bottom: 18px; }
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.card { background: var(--panel); border: 1px solid var(--border); padding: 18px; border-radius: 14px; }
.card h3 { margin: 0 0 8px; }
.card p { margin: 0; color: var(--muted); font-size: 14px; }
.chapter-list { display: grid; gap: 12px; }
.chapter { display: flex; gap: 16px; background: var(--panel); border: 1px solid var(--border); padding: 16px; border-radius: 12px; }
.chapter span { color: var(--yellow); font-weight: 700; }
.chapter h4 { margin: 0; }
.chapter p { margin: 4px 0 0; color: var(--muted); font-size: 14px; }
.notes { display: grid; gap: 10px; }
.note { background: #0f0f0f; border: 1px dashed var(--border); padding: 12px 14px; border-radius: 10px; color: var(--muted); }
.sub { color: var(--muted); }
.signup { display: flex; gap: 10px; margin-top: 14px; }
input { flex: 1; padding: 12px; border-radius: 10px; border: 1px solid var(--border); background: #0f0f0f; color: white; }
.fine { margin-top: 10px; color: var(--muted); font-size: 12px; }
footer { padding: 30px 32px; border-top: 1px solid var(--border); display: flex; justify-content: space-between; color: var(--muted); font-size: 13px; }

@media (max-width: 800px) {
  .grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 40px; }
  .cta { flex-direction: column; }
  .chapter { flex-direction: column; }
  .signup { flex-direction: column; }
  .nav { flex-direction: column; align-items: flex-start; gap: 10px; }
}