:root { color-scheme: light dark; }
body { margin: 0; font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; line-height: 1.6; background: #ffffff; color: #1a1a1a; }
main { max-width: 42rem; margin: 0 auto; padding: 2rem 1rem 4rem; }
h1 { font-size: 2rem; margin: 0 0 0.5rem; }
h2 { font-size: 1.2rem; margin: 2rem 0 0.5rem; }
.lead { font-size: 1.15rem; }
a { color: #0b57d0; }
footer { margin-top: 3rem; padding-top: 1rem; border-top: 1px solid #ccc; font-size: 0.9rem; }
@media (prefers-color-scheme: dark) {
  body { background: #121212; color: #e8e8e8; }
  a { color: #8ab4f8; }
  footer { border-top-color: #333; }
}