:root {
  --bg: #ffffff;
  --surface: #f4f7f9;
  --text: #0f172a;
  --muted: #5b6b7f;
  --line: #e2e8f0;
  --accent: #0f9e8e;
  --accent-ink: #ffffff;
  --accent-soft: #e6f6f4;
  --max: 720px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1b2a;
    --surface: #13263a;
    --text: #f1f5f9;
    --muted: #9fb0c3;
    --line: #22384f;
    --accent: #2dd4bf;
    --accent-ink: #062a26;
    --accent-soft: #123a3a;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
a { color: var(--accent); text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 16px; }

header.site {
  border-bottom: 1px solid var(--line);
}
header.site .wrap {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px; min-height: 60px; flex-wrap: wrap;
}
.brand {
  display: inline-flex; align-items: center; gap: 10px;
  color: var(--text); text-decoration: none; font-weight: 700; letter-spacing: -0.01em;
}
.brand .mark {
  width: 28px; height: 28px; border-radius: 8px; background: var(--accent);
  color: var(--accent-ink); display: grid; place-items: center; font-size: 15px; font-weight: 800;
}
nav.top { display: flex; gap: 18px; flex-wrap: wrap; font-size: 15px; }
nav.top a { color: var(--muted); text-decoration: none; }
nav.top a:hover, nav.top a[aria-current="page"] { color: var(--text); }

main { padding: 40px 0 64px; }

h1 { font-size: clamp(28px, 6vw, 40px); line-height: 1.15; letter-spacing: -0.02em; margin: 0 0 12px; }
h2 { font-size: 21px; line-height: 1.3; margin: 40px 0 10px; letter-spacing: -0.01em; }
h3 { font-size: 17px; margin: 24px 0 6px; }
p, ul, ol { margin: 0 0 14px; }
ul, ol { padding-left: 22px; }
li { margin-bottom: 6px; }
.lede { font-size: 18px; color: var(--muted); margin-bottom: 24px; }
.updated { color: var(--muted); font-size: 14px; margin-bottom: 28px; }
.small { font-size: 14px; color: var(--muted); }

.toc {
  background: var(--surface); border-radius: 12px; padding: 16px 20px; margin: 0 0 8px;
}
.toc ol { margin: 0; columns: 2 220px; column-gap: 24px; }
.toc li { margin-bottom: 4px; break-inside: avoid; }

.callout {
  background: var(--accent-soft); border-radius: 12px; padding: 14px 18px; margin: 18px 0;
}
.callout p:last-child { margin-bottom: 0; }

table { width: 100%; border-collapse: collapse; margin: 8px 0 18px; font-size: 15px; }
th, td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { font-weight: 600; color: var(--muted); font-size: 13px; text-transform: uppercase; letter-spacing: 0.04em; }
.table-scroll { overflow-x: auto; }

.btn {
  display: inline-block; background: var(--accent); color: var(--accent-ink);
  text-decoration: none; font-weight: 700; padding: 12px 20px; border-radius: 12px;
}
.btn.ghost { background: var(--surface); color: var(--text); }
.btns { display: flex; gap: 10px; flex-wrap: wrap; margin: 20px 0 8px; }

.plans { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 12px; margin: 16px 0; }
.plan { background: var(--surface); border-radius: 14px; padding: 18px; }
.plan h3 { margin: 0 0 2px; }
.plan .price { font-size: 15px; color: var(--muted); margin-bottom: 10px; }
.plan ul { padding-left: 18px; font-size: 15px; margin: 0; }

details { border-bottom: 1px solid var(--line); padding: 12px 0; }
details summary { cursor: pointer; font-weight: 600; list-style: none; position: relative; padding-right: 28px; }
details summary::-webkit-details-marker { display: none; }
details summary::after { content: "+"; position: absolute; right: 4px; top: -1px; color: var(--muted); font-size: 20px; }
details[open] summary::after { content: "–"; }
details > div { padding-top: 8px; }

footer.site { border-top: 1px solid var(--line); padding: 24px 0 40px; font-size: 14px; color: var(--muted); }
footer.site .links { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 8px; }
footer.site a { color: var(--muted); }

a.card-link { color: inherit; text-decoration: none; display: block; transition: transform .15s ease; }
a.card-link:hover { transform: translateY(-2px); }
a.card-link p { font-size: 15px; margin-bottom: 10px; }
a.card-link .more { color: var(--accent); font-weight: 600; font-size: 15px; }