:root { color-scheme: light dark; --fg: #1a1a1a; --bg: #fafafa; --muted: #666; }
@media (prefers-color-scheme: dark) { :root { --fg: #e8e8e8; --bg: #141414; --muted: #999; } }
body { font: 17px/1.55 -apple-system, system-ui, sans-serif; color: var(--fg); background: var(--bg);
       max-width: 40rem; margin: 0 auto; padding: 3rem 1rem; }
h1 { font-size: 1.6rem; line-height: 1.25; }
h2 { font-size: 1.1rem; margin-top: 2rem; }
a { color: inherit; }
small, .muted { color: var(--muted); }