:root {
  --fg: #1d2a24;
  --muted: #55645c;
  --bg: #ffffff;
  --panel: #f3f6f1;
  --accent: #2f6b3f;
  --line: #d8e0d6;
}
@media (prefers-color-scheme: dark) {
  :root {
    --fg: #e6ece6;
    --muted: #a9b5ad;
    --bg: #121713;
    --panel: #1b231d;
    --accent: #7fc28f;
    --line: #2c3a30;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, "Hiragino Sans", "Noto Sans JP", "Yu Gothic UI", sans-serif;
  line-height: 1.8;
}
a { color: var(--accent); }
header, main, footer { max-width: 880px; margin: 0 auto; padding: 0 16px; }
header { display: flex; justify-content: space-between; align-items: center; padding-top: 20px; padding-bottom: 12px; border-bottom: 1px solid var(--line); }
header .brand { font-weight: 700; font-size: 1.25rem; color: var(--fg); text-decoration: none; letter-spacing: .02em; }
header nav a { margin-left: 16px; font-size: .95rem; }
main { padding-top: 24px; padding-bottom: 48px; }
h1 { font-size: 1.75rem; line-height: 1.4; margin: .4em 0 .6em; }
h2 { font-size: 1.25rem; margin: 2em 0 .6em; padding-bottom: .2em; border-bottom: 1px solid var(--line); }
h3 { font-size: 1.05rem; margin: 1.4em 0 .4em; }
.lead { font-size: 1.1rem; color: var(--muted); }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 12px; margin: 16px 0; }
.card { background: var(--panel); border: 1px solid var(--line); border-radius: 8px; padding: 14px 16px; }
.card h3 { margin-top: 0; }
table { width: 100%; border-collapse: collapse; margin: 12px 0; font-size: .95rem; }
th, td { text-align: left; vertical-align: top; padding: 8px; border-bottom: 1px solid var(--line); }
th { width: 30%; color: var(--muted); font-weight: 600; }
footer { border-top: 1px solid var(--line); padding-top: 16px; padding-bottom: 32px; color: var(--muted); font-size: .9rem; }
@media (max-width: 560px) {
  header { flex-direction: column; align-items: flex-start; gap: 6px; }
  header nav a { margin: 0 16px 0 0; }
  th { width: auto; display: block; border-bottom: 0; padding-bottom: 0; }
  td { display: block; padding-top: 2px; }
}