:root {
  color-scheme: light dark;
  --fg: #1a1c1e;
  --muted: #5a5f65;
  --bg: #ffffff;
  --rule: #e2e5e9;
  --link: #0b57d0;
}

@media (prefers-color-scheme: dark) {
  :root {
    --fg: #e3e2e6;
    --muted: #a8adb4;
    --bg: #131417;
    --rule: #2c2f34;
    --link: #a8c7fa;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans",
    "Noto Sans JP", "Yu Gothic", sans-serif;
  line-height: 1.9;
  font-size: 16px;
}

main {
  max-width: 44rem;
  margin: 0 auto;
  padding: 2.5rem 1.25rem 4rem;
}

h1 {
  font-size: 1.6rem;
  line-height: 1.5;
  margin: 0 0 1.5rem;
}

h2 {
  font-size: 1.15rem;
  margin: 2.5rem 0 0.75rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--rule);
}

h3 {
  font-size: 1rem;
  margin: 1.75rem 0 0.5rem;
}

p, ul { margin: 0 0 1rem; }

ul { padding-inline-start: 1.5rem; }

li { margin-bottom: 0.4rem; }

strong { font-weight: 600; }

a { color: var(--link); }

.updated {
  color: var(--muted);
  font-size: 0.9rem;
}

.footer-nav {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--rule);
  font-size: 0.9rem;
  color: var(--muted);
}