:root {
  --bg: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --border: #e2e8f0;
  --accent: #059669;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --text: #f1f5f9;
    --muted: #94a3b8;
    --border: #26324a;
    --accent: #10b981;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
main { max-width: 720px; margin: 0 auto; padding: 40px 16px 64px; }
header { display: flex; align-items: center; gap: 10px; margin-bottom: 32px; }
header a { color: var(--text); text-decoration: none; font-weight: 700; font-size: 20px; }
nav { margin-left: auto; display: flex; gap: 16px; font-size: 14px; }
nav a { color: var(--muted); text-decoration: none; }
nav a:hover { color: var(--accent); }
h1 { font-size: 32px; line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 20px; margin: 32px 0 8px; }
p, li { color: var(--text); }
.muted { color: var(--muted); }
a { color: var(--accent); }
ul { padding-left: 20px; }
footer { margin-top: 48px; padding-top: 16px; border-top: 1px solid var(--border); font-size: 14px; color: var(--muted); }
.hero { font-size: 20px; color: var(--muted); margin-bottom: 24px; }