:root { color-scheme: light dark; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
body { margin: 0; background: #f4f6f8; color: #17202a; line-height: 1.65; }
main { max-width: 820px; margin: 0 auto; padding: 48px 24px 72px; background: #fff; min-height: 100vh; }
h1 { font-size: 2.25rem; line-height: 1.15; margin-bottom: .25rem; }
h2 { margin-top: 2rem; font-size: 1.35rem; }
h3 { margin-top: 1.4rem; font-size: 1.05rem; }
a { color: #0969da; }
.meta { color: #59636e; margin-top: 0; }
.notice { border-left: 4px solid #d97706; background: #fff7ed; padding: 12px 16px; margin: 22px 0; }
.nav { display: flex; gap: 18px; padding-bottom: 18px; border-bottom: 1px solid #d8dee4; }
footer { margin-top: 48px; padding-top: 18px; border-top: 1px solid #d8dee4; color: #59636e; }
@media (prefers-color-scheme: dark) {
  body { background: #0d1117; color: #e6edf3; }
  main { background: #161b22; }
  a { color: #58a6ff; }
  .meta, footer { color: #9da7b3; }
  .notice { background: #302311; border-left-color: #f59e0b; }
  .nav, footer { border-color: #30363d; }
}