:root {
  --bg: #fbfbfa;
  --surface: #ffffff;
  --text: #16181d;
  --text-2: #43474f;
  --muted: #646a75;
  --line: #e3e4e8;
  --accent: #0b7a6c;
  --accent-soft: #e7f4f1;
  --note: #fff7e6;
  --note-line: #f0d9a8;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0d12;
    --surface: #12151c;
    --text: #e8eaf0;
    --text-2: #c2c6d1;
    --muted: #9298a8;
    --line: #262b38;
    --accent: #5ee6d0;
    --accent-soft: #10241f;
    --note: #221d10;
    --note-line: #4a3d1d;
    color-scheme: dark;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/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; }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 3px; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; background: var(--surface); padding: 6px 10px; z-index: 10; }

header.site { border-bottom: 1px solid var(--line); background: var(--surface); }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 20px; }
header.site .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding-top: 14px; padding-bottom: 14px; }
.brand { font-weight: 700; letter-spacing: -0.01em; font-size: 18px; color: var(--text); text-decoration: none; }
.brand span { color: var(--accent); }
nav.top { display: flex; gap: 6px 18px; flex-wrap: wrap; font-size: 15px; }
nav.top a { color: var(--text-2); text-decoration: none; }
nav.top a:hover, nav.top a[aria-current="page"] { color: var(--accent); }

main { padding: 40px 0 56px; }
h1 { font-size: clamp(28px, 5vw, 36px); line-height: 1.2; letter-spacing: -0.02em; margin: 0 0 8px; }
h2 { font-size: 21px; line-height: 1.3; margin: 40px 0 10px; padding-top: 8px; }
h3 { font-size: 17px; margin: 24px 0 6px; }
p, ul, ol { margin: 0 0 14px; color: var(--text-2); }
li { margin-bottom: 6px; }
strong { color: var(--text); }
.lead { font-size: 19px; color: var(--text-2); }
.meta { color: var(--muted); font-size: 15px; margin-bottom: 28px; }

.toc { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 16px 20px; margin: 24px 0 8px; }
.toc p { margin: 0 0 6px; font-weight: 600; color: var(--text); font-size: 15px; }
.toc ol { margin: 0; padding-left: 22px; columns: 2; column-gap: 28px; font-size: 15px; }
.toc li { break-inside: avoid; margin-bottom: 4px; }

.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 14px; margin: 28px 0; }
.card { display: block; background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 18px; text-decoration: none; color: var(--text); }
.card:hover { border-color: var(--accent); }
.card strong { display: block; margin-bottom: 4px; font-size: 17px; }
.card span { color: var(--muted); font-size: 15px; line-height: 1.5; display: block; }

.box { background: var(--accent-soft); border-radius: 12px; padding: 16px 20px; margin: 20px 0; }
.box p:last-child, .box ul:last-child, .box ol:last-child { margin-bottom: 0; }
.note { background: var(--note); border: 1px solid var(--note-line); border-radius: 12px; padding: 14px 18px; margin: 20px 0; font-size: 15.5px; }
.note p:last-child { margin-bottom: 0; }

.btn { display: inline-block; background: var(--accent); color: #fff; padding: 11px 18px; border-radius: 10px; text-decoration: none; font-weight: 600; }
@media (prefers-color-scheme: dark) { .btn { color: #062a24; } }
.btn:hover { filter: brightness(1.08); }

.table-wrap { overflow-x: auto; margin: 0 0 16px; }
table { border-collapse: collapse; width: 100%; font-size: 15px; }
th, td { text-align: left; vertical-align: top; padding: 10px 12px; border-bottom: 1px solid var(--line); color: var(--text-2); }
th { color: var(--text); font-weight: 600; }

footer.site { border-top: 1px solid var(--line); padding: 24px 0 32px; color: var(--muted); font-size: 14.5px; }
footer.site nav { display: flex; flex-wrap: wrap; gap: 6px 18px; margin-bottom: 8px; }
footer.site a { color: var(--text-2); }
footer.site p { color: var(--muted); margin: 0; }

@media (max-width: 560px) {
  body { font-size: 16px; }
  main { padding-top: 28px; }
  .toc ol { columns: 1; }
}
@media print {
  header.site nav, footer.site nav, .skip { display: none; }
  body { background: #fff; color: #000; }
}