:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #6b6b6b;
  --border: #e5e5e5;
  --accent: #3a5a78;
  --accent-bg: #f4f7fa;
  --max-width: 760px;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  padding: 24px 16px 64px;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Hiragino Sans", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  font-size: 15px;
  line-height: 1.75;
  color: var(--fg);
  background: var(--bg);
}

main {
  max-width: var(--max-width);
  margin: 0 auto;
}

nav.top {
  max-width: var(--max-width);
  margin: 0 auto 24px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

nav.top .group { display: flex; gap: 12px; }

nav.top a {
  font-size: 13px;
  color: var(--muted);
  text-decoration: none;
}

nav.top a.active {
  color: var(--accent);
  font-weight: 600;
}

nav.top a:hover { color: var(--accent); }

h1 {
  font-size: 22px;
  margin: 0 0 8px;
  letter-spacing: 0.02em;
}

.meta {
  color: var(--muted);
  font-size: 13px;
  margin: 0 0 24px;
}

h2 {
  font-size: 17px;
  margin: 32px 0 8px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}

h3 {
  font-size: 15px;
  margin: 20px 0 6px;
  color: var(--accent);
}

p { margin: 0 0 10px; }

ul, ol { padding-left: 1.3em; margin: 6px 0 12px; }
li { margin: 4px 0; }

a {
  color: var(--accent);
  word-break: break-all;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 8px 0 16px;
  font-size: 14px;
}

th, td {
  border: 1px solid var(--border);
  padding: 8px 10px;
  text-align: left;
  vertical-align: top;
}

th {
  background: var(--accent-bg);
  font-weight: 600;
}

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
  background: var(--accent-bg);
  padding: 1px 5px;
  border-radius: 4px;
}

footer {
  max-width: var(--max-width);
  margin: 48px auto 0;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 12px;
  text-align: center;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --fg: #e6e6e6;
    --muted: #9aa0a6;
    --border: #2a2d33;
    --accent: #87a9c7;
    --accent-bg: #1a1e25;
  }
}

@media (max-width: 480px) {
  body { font-size: 14px; padding: 16px 14px 48px; }
  h1 { font-size: 20px; }
  h2 { font-size: 16px; }
  table { font-size: 13px; }
}