:root {
  --bg: #ffffff;
  --surface: #f6f7f9;
  --border: #e2e6ec;
  --text: #0d1320;
  --text-2: #465161;
  --muted: #6b7584;
  --accent: #2563eb;
  --accent-text: #ffffff;
  --hover: #edf0f5;
  --video-bg: #0a0f18;
  --sans: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --topbar: 56px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0a0f18;
    --surface: #0f1622;
    --border: #1e2836;
    --text: #f1f4f8;
    --text-2: #b4beca;
    --muted: #7d8a9c;
    --accent: #3b82f6;
    --accent-text: #ffffff;
    --hover: #162030;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0a0f18;
  --surface: #0f1622;
  --border: #1e2836;
  --text: #f1f4f8;
  --text-2: #b4beca;
  --muted: #7d8a9c;
  --accent: #3b82f6;
  --accent-text: #ffffff;
  --hover: #162030;
  color-scheme: dark;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-padding-top: calc(var(--topbar) + 16px); -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 15px/1.6 var(--sans); }
a { color: var(--accent); }
code { font: 0.86em var(--mono); color: var(--text); background: var(--surface); border: 1px solid var(--border); padding: 0 4px; border-radius: 4px; overflow-wrap: anywhere; }
strong { color: var(--text); font-weight: 600; }
.skip { position: absolute; left: -9999px; top: 8px; z-index: 20; background: var(--accent); color: var(--accent-text); padding: 8px 12px; }
.skip:focus { left: 8px; }

.topbar { position: sticky; top: 0; z-index: 10; height: var(--topbar); display: flex; align-items: center; gap: 24px; padding: 0 20px; background: var(--bg); border-bottom: 1px solid var(--border); }
.brand { display: flex; color: var(--text); }
.brand svg { height: 22px; width: auto; }
.languages { display: flex; gap: 2px; margin-left: auto; }
.languages a { color: var(--text-2); text-decoration: none; font-size: 13px; padding: 5px 9px; border-radius: 6px; white-space: nowrap; }
.languages a:hover { background: var(--hover); color: var(--text); }
.languages a[aria-current] { color: var(--text); background: var(--surface); box-shadow: inset 0 0 0 1px var(--border); font-weight: 500; }
.links { display: flex; align-items: center; gap: 14px; font-size: 13px; }
.links a { color: var(--text-2); text-decoration: none; white-space: nowrap; }
.links a:hover { color: var(--text); }
.links .button { background: var(--accent); color: var(--accent-text); padding: 6px 12px; border-radius: 6px; font-weight: 500; }
.links .button:hover { color: var(--accent-text); filter: brightness(1.08); }

.layout { display: grid; grid-template-columns: 250px minmax(0, 1fr); max-width: 1500px; margin: 0 auto; }
@media (min-width: 1400px) { .layout { grid-template-columns: 250px minmax(0, 1fr) 220px; } }

.sidebar { position: sticky; top: var(--topbar); height: calc(100dvh - var(--topbar)); overflow-y: auto; border-right: 1px solid var(--border); background: var(--surface); }
.search { padding: 16px; }
.search label { display: block; font-size: 11px; font-weight: 600; color: var(--text-2); margin-bottom: 6px; }
.search input { width: 100%; font: inherit; font-size: 14px; color: var(--text); background: var(--bg); border: 1px solid var(--border); border-radius: 6px; padding: 7px 10px; }
.search input:focus { outline: 2px solid var(--accent); outline-offset: -1px; }
.nav-details > summary { display: none; }
.nav { border-top: 1px solid var(--border); padding: 12px 8px; }
.nav-group { margin-bottom: 18px; }
.nav-label { margin: 0; padding: 0 8px 6px; font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.04em; color: var(--muted); }
.nav a { display: block; padding: 5px 8px; border-radius: 5px; color: var(--text-2); text-decoration: none; font-size: 14px; }
.nav a:hover { background: var(--hover); color: var(--text); }
.nav-summary { display: none; font-size: 12px; line-height: 1.45; color: var(--muted); margin-top: 2px; }
.nav.searching .nav-summary { display: block; }
.nav.searching .nav-label { display: none; }
.nav.searching .nav-group { margin-bottom: 0; }
.nav.searching a { padding: 8px; }
.nav-count { margin: 0; padding: 0 8px 8px; font-size: 11px; font-weight: 600; text-transform: uppercase; color: var(--muted); }

.article { min-width: 0; width: 100%; max-width: 980px; padding: 40px 48px 80px; }
.page-head { border-bottom: 1px solid var(--border); padding-bottom: 28px; margin-bottom: 8px; }
.page-head h1 { margin: 0; font-size: 36px; line-height: 1.2; font-weight: 600; letter-spacing: -0.01em; }
.page-head p { margin: 14px 0 0; max-width: 46em; font-size: 16px; line-height: 1.7; color: var(--text-2); }
.section { padding: 36px 0; border-top: 1px solid var(--border); }
.section.first, .page-head + .section { border-top: 0; }
.section h2 { margin: 0 0 18px; font-size: 21px; font-weight: 600; }
.sub { margin: 30px 0 12px; font-size: 16px; font-weight: 600; }
.prose p, .intro, .list li { color: var(--text-2); font-size: 15px; line-height: 1.75; }
.prose p { margin: 0 0 14px; }
.intro { margin: 0 0 20px; }
.list { padding-left: 22px; }
.list li { margin-bottom: 8px; }
.note { font-size: 13px; color: var(--muted); }

.workflow { border: 1px solid var(--border); border-radius: 10px; overflow: hidden; background: var(--surface); }
.workflow video { display: block; width: 100%; height: auto; aspect-ratio: 1440 / 930; background: var(--video-bg); }
.chapters { padding: 14px 8px 8px; border-top: 1px solid var(--border); }
.chapters ol { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }
.chapters button { display: flex; gap: 10px; width: 100%; text-align: left; font: inherit; font-size: 13px; color: var(--text-2); background: none; border: 0; border-radius: 5px; padding: 6px 8px; cursor: pointer; }
.chapters button:hover { background: var(--hover); color: var(--text); }
.chapters button[aria-current] { color: var(--text); background: var(--hover); }
.chapters button[aria-current] .time { color: var(--accent); }
.time { font: 12px/1.7 var(--mono); color: var(--muted); min-width: 38px; }

.tutorial { margin: 26px 0; }
.tutorial-head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; padding: 8px 12px; border: 1px solid var(--border); border-bottom: 0; background: var(--surface); font-size: 14px; font-weight: 600; border-radius: 8px 8px 0 0; }
.tutorial video { display: block; width: 100%; height: auto; aspect-ratio: 1440 / 930; background: var(--video-bg); border-left: 1px solid var(--border); border-right: 1px solid var(--border); }
.tutorial-desc { margin: 0; padding: 8px 12px; border: 1px solid var(--border); border-top: 0; font-size: 13px; line-height: 1.55; color: var(--text-2); border-radius: 0 0 8px 8px; }
.tag { font: 11px/1.8 var(--mono); color: var(--muted); white-space: nowrap; }

.cards { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); margin-top: 24px; }
.cards > div { padding: 16px; }
.cards > div + div { border-left: 1px solid var(--border); }
.cards h3 { margin: 0 0 4px; font-size: 14px; font-weight: 600; }
.cards p { margin: 0; font-size: 13px; line-height: 1.55; color: var(--text-2); }

.index { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: var(--border); border: 1px solid var(--border); border-radius: 8px; overflow: hidden; }
.index li { background: var(--bg); }
.index a { display: flex; gap: 12px; height: 100%; padding: 12px 16px; text-decoration: none; }
.index a:hover { background: var(--hover); }
.index-title { display: block; font-size: 14px; font-weight: 500; color: var(--text); }
.index-desc { display: block; font-size: 12px; line-height: 1.5; color: var(--muted); margin-top: 2px; }

.steps { list-style: none; margin: 0; padding: 0; }
.steps > li { display: grid; grid-template-columns: 34px minmax(0, 1fr); gap: 12px; padding: 18px 0; border-top: 1px solid var(--border); }
.steps > li:first-child { border-top: 0; padding-top: 0; }
.step-head { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: baseline; gap: 8px; }
.step-head h3 { margin: 0; font-size: 16px; font-weight: 600; }
.steps p { margin: 8px 0 4px; font-size: 14px; line-height: 1.65; color: var(--text-2); }
.steps .result { margin: 0; font-size: 13px; color: var(--muted); }
.steps .result strong { color: var(--text-2); font-weight: 500; }

.table-wrap { overflow-x: auto; margin: 20px 0; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
table { width: 100%; min-width: 620px; border-collapse: collapse; font-size: 14px; text-align: left; }
th { background: var(--surface); font-size: 12px; font-weight: 600; color: var(--text-2); padding: 8px 12px; border-bottom: 1px solid var(--border); }
td { padding: 11px 12px; vertical-align: top; line-height: 1.5; color: var(--text-2); border-bottom: 1px solid var(--border); }
tr:last-child td { border-bottom: 0; }
td:first-child { color: var(--text); font-weight: 500; }

.glossary { margin: 0; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.glossary > div { display: grid; grid-template-columns: 170px minmax(0, 1fr); gap: 20px; padding: 12px 0; border-bottom: 1px solid var(--border); }
.glossary > div:last-child { border-bottom: 0; }
.glossary dt { font-size: 14px; font-weight: 600; }
.glossary dd { margin: 0; font-size: 14px; line-height: 1.6; color: var(--text-2); }

.faq { border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.faq details { border-bottom: 1px solid var(--border); }
.faq details:last-child { border-bottom: 0; }
.faq summary { cursor: pointer; list-style: none; padding: 12px 4px; font-size: 14px; font-weight: 500; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::before { content: '+'; display: inline-block; width: 18px; font-family: var(--mono); color: var(--muted); }
.faq details[open] summary::before { content: '−'; }
.faq p { margin: 0 16px 14px 22px; font-size: 14px; line-height: 1.65; color: var(--text-2); }

.toc { display: none; border-left: 1px solid var(--border); background: var(--surface); }
.toc > div { position: sticky; top: var(--topbar); padding: 16px; }
.toc a { display: block; padding: 4px 0; font-size: 12px; color: var(--text-2); text-decoration: none; }
.toc a:hover { color: var(--text); }
@media (min-width: 1400px) { .toc { display: block; } }

@media (max-width: 1000px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
  .sidebar { position: static; height: auto; border-right: 0; border-bottom: 1px solid var(--border); }
  .nav-details > summary { display: block; cursor: pointer; padding: 12px 16px; border-top: 1px solid var(--border); font-size: 14px; font-weight: 500; }
  .article { padding: 28px 24px 64px; }
}
@media (max-width: 720px) {
  .topbar { gap: 12px; padding: 0 16px; height: auto; min-height: var(--topbar); flex-wrap: wrap; padding-top: 10px; padding-bottom: 10px; position: static; }
  html { scroll-padding-top: 16px; }
  .languages { order: 3; width: 100%; margin-left: -9px; overflow-x: auto; }
  .links { margin-left: auto; }
  .links a:not(.button) { display: none; }
  .article { padding: 24px 16px 56px; }
  .page-head h1 { font-size: 28px; }
  .cards, .index { grid-template-columns: 1fr; }
  .cards > div + div { border-left: 0; border-top: 1px solid var(--border); }
  .glossary > div { grid-template-columns: 1fr; gap: 4px; }
  .chapters ol { grid-template-columns: 1fr; }
}