:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #555;
  --accent: #0f4c81;
  --border: #e0e0e0;
  --card: #f7f8fa;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111417;
    --fg: #e8e8e8;
    --muted: #9aa0a6;
    --accent: #7ab3e0;
    --border: #2c3136;
    --card: #1a1f24;
  }
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--fg);
  font-family: "Hiragino Sans", "Yu Gothic", system-ui, sans-serif;
  line-height: 1.8;
}
main { max-width: 720px; margin: 0 auto; padding: 2rem 1.25rem 4rem; }
header.site {
  border-bottom: 1px solid var(--border);
  padding: 1rem 1.25rem;
}
header.site .inner { max-width: 720px; margin: 0 auto; display: flex; justify-content: space-between; align-items: baseline; flex-wrap: wrap; gap: .5rem; }
header.site a { color: var(--fg); text-decoration: none; font-weight: 700; }
header.site nav a { color: var(--muted); font-weight: 400; font-size: .85rem; margin-left: 1rem; }
h1 { font-size: 1.6rem; margin: 1.5rem 0 .5rem; line-height: 1.4; }
h2 { font-size: 1.15rem; margin: 2rem 0 .75rem; padding-left: .6rem; border-left: 4px solid var(--accent); }
p, ul, ol { margin-bottom: 1rem; color: var(--fg); }
ul, ol { padding-left: 1.5rem; }
.lead { color: var(--muted); font-size: .95rem; }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin: 1rem 0;
}
.updated { color: var(--muted); font-size: .8rem; margin-top: 2rem; }
footer.site {
  border-top: 1px solid var(--border);
  padding: 1.5rem 1.25rem;
  text-align: center;
  color: var(--muted);
  font-size: .85rem;
}
footer.site a { color: var(--muted); margin: 0 .5rem; }
code { background: var(--card); padding: .1em .35em; border-radius: 4px; font-size: .9em; }