:root {
  --bg: #f8fafc;
  --text: #0f172a;
  --muted: #475569;
  --link: #1e5bb8;
  --card: #ffffff;
  --border: #e2e8f0;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --text: #e2e8f0;
    --muted: #94a3b8;
    --link: #22d3ee;
    --card: #111a2e;
    --border: #1e293b;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
a { color: var(--link); }
.hero, .doc {
  width: 100%;
  max-width: 680px;
  margin: 0 auto;
  padding: 48px 16px;
  flex: 1;
}
.hero { text-align: center; }
.logo { border-radius: 22px; }
.hero h1 {
  font-size: 44px;
  margin: 16px 0 4px;
  background: linear-gradient(135deg, #1e3a8a, #22d3ee);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.tagline { font-size: 20px; color: var(--muted); margin-top: 0; }
.features {
  list-style: none;
  padding: 0;
  margin: 24px auto;
  display: inline-block;
  text-align: left;
}
.features li::before { content: "✓  "; color: #22d3ee; font-weight: 700; }
.note { color: var(--muted); font-size: 14px; }
.doc h1 { margin-bottom: 0; }
.doc h2 { margin-top: 32px; }
.doc h3 { margin-bottom: 0; }
.meta { color: var(--muted); margin-top: 4px; }
.back { text-decoration: none; font-size: 14px; }
footer {
  text-align: center;
  padding: 24px 16px;
  border-top: 1px solid var(--border);
  font-size: 14px;
  color: var(--muted);
}
footer a { margin: 0 6px; }