:root { --bg: #ffffff; --fg: #1d1d1f; --muted: #6b6b70; --link: #1a5fd0; }
@media (prefers-color-scheme: dark) {
  :root { --bg: #111214; --fg: #ececee; --muted: #9a9aa2; --link: #7fb0ff; }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--fg); font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
main { max-width: 680px; margin: 0 auto; padding: 48px 16px 64px; }
h1 { font-size: 1.8rem; margin: 0 0 16px; }
h2 { font-size: 1.15rem; margin: 28px 0 8px; }
a { color: var(--link); }
.muted { color: var(--muted); }
nav { display: flex; gap: 20px; margin-top: 28px; }
footer { margin-top: 40px; color: var(--muted); font-size: 0.95rem; }