:root {
  --bg: #ffffff;
  --fg: #1a1f24;
  --muted: #566170;
  --link: #0b5cab;
  --rule: #d8dee6;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12161b;
    --fg: #e7ebf0;
    --muted: #9aa6b4;
    --link: #7ab4ee;
    --rule: #2b333d;
  }
}
* { box-sizing: border-box; }
html { background: var(--bg); }
body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
main { flex: 1; width: 100%; max-width: 40rem; margin: 0 auto; padding: 4rem 1.25rem 2rem; }
h1 { margin: 0 0 1.5rem; font-size: 2rem; letter-spacing: 0.08em; }
section { padding: 1rem 0; border-top: 1px solid var(--rule); }
p { margin: 0 0 0.75rem; }
a { color: var(--link); }
footer { padding: 1.25rem; border-top: 1px solid var(--rule); color: var(--muted); font-size: 0.875rem; text-align: center; }
footer a { color: inherit; }