:root {
  --bg: #ffffff;
  --fg: #1d2330;
  --muted: #5b6475;
  --line: #e3e6ec;
  --card: #f6f7f9;
  --accent: #2f6fde;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171c;
    --fg: #e7e9ee;
    --muted: #a2aab8;
    --line: #2a2f37;
    --card: #1b1f26;
    --accent: #7aa7ff;
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

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

header.site,
main,
footer {
  max-width: 820px;
  margin: 0 auto;
  padding-left: 16px;
  padding-right: 16px;
}

header.site {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  padding-top: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

header.site .brand {
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--fg);
  text-decoration: none;
}

header.site .tagline { color: var(--muted); font-size: 0.9rem; letter-spacing: 0.02em; }

main { padding-top: 24px; padding-bottom: 48px; }

h1 { font-size: 1.9rem; line-height: 1.25; margin: 8px 0 4px; }
h2 { font-size: 1.35rem; line-height: 1.3; margin: 40px 0 12px; padding-top: 20px; border-top: 1px solid var(--line); }
/* 頁面直接從 h2 開始（首頁）：頁首已經有底線，不再多畫一條分隔線 */
main > h2:first-child { margin-top: 8px; padding-top: 0; border-top: none; }
h3 { font-size: 1.1rem; margin: 28px 0 8px; }
h4 { font-size: 1rem; margin: 20px 0 6px; }

p, li { overflow-wrap: anywhere; }

.updated { color: var(--muted); margin: 0 0 24px; }
.lead { font-size: 1.05rem; }

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
  margin: 12px 0;
}

.card,
.box {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 16px;
}

.card h3 { margin: 0 0 8px; font-size: 1rem; }
.card p { margin: 6px 0; font-size: 0.95rem; }
.card .label { color: var(--muted); }

.box p:first-child { margin-top: 0; }
.box p:last-child { margin-bottom: 0; }

.toc ol { margin: 4px 0; padding-left: 22px; }

dl.meta {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 4px 12px;
  margin: 8px 0;
}
dl.meta dt { color: var(--muted); }
dl.meta dd { margin: 0; }

.links { display: flex; flex-wrap: wrap; gap: 10px; margin: 16px 0; }
.links a {
  display: inline-block;
  padding: 10px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--card);
  text-decoration: none;
}

footer {
  padding-top: 20px;
  padding-bottom: 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.9rem;
}