:root {
  --bg: #f7f7f5;
  --surface: #ffffff;
  --text: #1c1d1f;
  --muted: #5d6066;
  --line: #e3e3df;
  --accent: #0f6e5a;
  --accent-soft: #e3f1ed;
  --radius: 14px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121314;
    --surface: #1b1c1e;
    --text: #ececea;
    --muted: #a2a5ab;
    --line: #2c2e31;
    --accent: #5cc7ab;
    --accent-soft: #1c2f2a;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 16px; }

header.top { border-bottom: 1px solid var(--line); background: var(--surface); }
header.top .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; flex-wrap: wrap; }
.brand { font-weight: 700; font-size: 18px; color: var(--text); text-decoration: none; letter-spacing: -0.01em; }
.brand span { color: var(--accent); }
nav a { color: var(--muted); text-decoration: none; margin-left: 18px; font-size: 15px; }
nav a:first-child { margin-left: 0; }
nav a:hover, nav a[aria-current] { color: var(--text); }

.hero { padding: 56px 0 28px; }
.hero h1 { font-size: clamp(28px, 5vw, 40px); line-height: 1.15; margin: 0 0 12px; letter-spacing: -0.02em; }
.hero p { color: var(--muted); max-width: 640px; margin: 0; font-size: 17px; }

section { padding: 24px 0; }
section > h2 { font-size: 20px; margin: 0 0 4px; }
section > .sub { color: var(--muted); margin: 0 0 18px; font-size: 15px; }

.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 14px; }
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  display: flex; flex-direction: column; gap: 6px;
}
.card h3 { margin: 0; font-size: 16px; }
.card p { margin: 0; color: var(--muted); font-size: 14.5px; flex: 1; }
.card .meta { display: flex; justify-content: space-between; align-items: center; gap: 8px; margin-top: 8px; font-size: 13px; }
.tag { background: var(--accent-soft); color: var(--accent); border-radius: 999px; padding: 2px 10px; font-weight: 600; }
.tag.staff { background: transparent; color: var(--muted); border: 1px solid var(--line); }
.card a.open { font-weight: 600; text-decoration: none; }
.card a.open:hover { text-decoration: underline; }

.doc { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px clamp(18px, 4vw, 40px); margin: 32px 0; }
.doc h1 { margin-top: 0; font-size: clamp(26px, 4vw, 32px); letter-spacing: -0.02em; }
.doc h2 { font-size: 18px; margin-top: 28px; }
.doc .updated { color: var(--muted); font-size: 14px; }
.doc li { margin: 4px 0; }

footer { border-top: 1px solid var(--line); margin-top: 40px; padding: 24px 0 40px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; }
footer a { color: var(--muted); margin-right: 16px; }