: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: 2.5rem 1.25rem 4rem; }
h1 { font-size: 1.9rem; line-height: 1.25; margin-top: 0; }
h2 { font-size: 1.25rem; margin-top: 2rem; }
a { color: #0b4fa8; }
a:focus-visible { outline: 3px solid #0b4fa8; outline-offset: 2px; }
nav { font-size: 0.95rem; margin-bottom: 2rem; }
footer { margin-top: 3rem; font-size: 0.9rem; color: #444444; border-top: 1px solid #cccccc; padding-top: 1rem; }
@media (prefers-color-scheme: dark) {
  body { background: #121212; color: #e8e8e8; }
  a { color: #8ab4f8; }
  a:focus-visible { outline-color: #8ab4f8; }
  footer { color: #b8b8b8; border-top-color: #444444; }
}