:root {
  --bg: #ffffff;
  --fg: #0f172a;
  --muted: #475569;
  --link: #0e7490;
  --code: #f1f5f9;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f172a;
    --fg: #e2e8f0;
    --muted: #94a3b8;
    --link: #38bdf8;
    --code: #1e293b;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 "Segoe UI", system-ui, -apple-system, sans-serif;
}
main { max-width: 720px; margin: 0 auto; padding: 40px 16px 64px; }
h1 { font-size: 1.9rem; line-height: 1.25; margin: 0 0 8px; }
h2 { font-size: 1.15rem; margin: 32px 0 8px; }
.lead { font-size: 1.1rem; color: var(--muted); }
.muted, .crumb { color: var(--muted); font-size: .9rem; }
a { color: var(--link); }
code { background: var(--code); padding: 1px 5px; border-radius: 4px; font-size: .9em; }
li { margin: 4px 0; }