:root { color-scheme: light dark; }
* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif;
  line-height: 1.8;
  color: #1a1a1a;
  background: #f6f4f1;
}
.content { max-width: 720px; margin: 0 auto; padding: 48px 24px 96px; }
h1 { font-size: 2rem; margin: 24px 0 8px; }
h2 { font-size: 1.25rem; margin: 32px 0 8px; }
p, ul { margin: 12px 0; }
ul { padding-left: 1.4em; }
a { color: #c24e0a; }
.tagline { font-size: 1.2rem; font-weight: 700; }
.update-date { color: #6b6b6b; font-size: 0.9rem; }
.back-link { display: inline-block; margin-bottom: 16px; }
.footer-links { margin-top: 48px; color: #6b6b6b; }
@media (prefers-color-scheme: dark) {
  body { color: #f0f0f0; background: #111; }
  a { color: #ff8a4d; }
  .update-date, .footer-links { color: #9a9a9a; }
}