:root { --bg: #fafafa; --fg: #1a1a1a; --muted: #666; --link: #2457d6; }
@media (prefers-color-scheme: dark) {
  :root { --bg: #141414; --fg: #e8e8e8; --muted: #9a9a9a; --link: #7aa2ff; }
}
body { margin: 0; background: var(--bg); color: var(--fg); font: 16px/1.6 system-ui, -apple-system, "Segoe UI", sans-serif; }
main { max-width: 680px; margin: 0 auto; padding: 48px 16px; }
h1 { font-size: 2rem; margin: 0 0 8px; }
h2 { font-size: 1.15rem; margin-top: 32px; }
.lead { font-size: 1.1rem; }
.muted { color: var(--muted); }
a { color: var(--link); }