:root {
  --ink: #1d1d1f;
  --muted: #6e6e73;
  --line: #e3e3e8;
  --surface: #f5f5f7;
  --night: #000;
  --night-line: rgba(255, 255, 255, .12);
  --night-muted: #a1a1a6;
  --blue: #0071e3;
  --blue-bright: #2997ff;
  --tile: #ebf3fc;
  --radius: 22px;
  --wrap: 1180px;
  --nav-h: 52px;
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  color-scheme: light;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 16px); -webkit-text-size-adjust: 100%; }
body { margin: 0; font-family: var(--font); color: var(--ink); background: #fff; line-height: 1.65; -webkit-font-smoothing: antialiased; }
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
:focus-visible { outline: 2px solid var(--blue-bright); outline-offset: 3px; border-radius: 6px; }
code { font-family: var(--mono); font-size: .86em; padding: .12em .42em; border-radius: 6px; background: rgba(0, 0, 0, .06); white-space: nowrap; }
h1, h2, h3 { line-height: 1.2; }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }
.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }

/* ---------- 导航 ---------- */
.nav {
  position: fixed; inset: 0 0 auto; z-index: 100; height: var(--nav-h);
  background: rgba(0, 0, 0, .72);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, .08);
  color: #f5f5f7;
}
.nav-inner { display: flex; align-items: center; gap: 24px; height: 100%; }
.brand { display: flex; align-items: center; gap: 10px; margin-right: auto; font-size: 17px; font-weight: 600; letter-spacing: -.01em; color: #fff; }
.brand .mark { width: 28px; height: 28px; }
.nav-links { display: flex; align-items: center; gap: 30px; font-size: 14px; }
.nav-links a { color: rgba(255, 255, 255, .8); transition: color .2s; }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: #fff; }
.gh-pill {
  display: inline-flex; align-items: center; gap: 8px; height: 32px; padding: 0 14px; border-radius: 999px;
  background: rgba(255, 255, 255, .12); color: #fff !important; font-size: 13px; font-weight: 600;
  transition: background .2s;
}
.gh-pill:hover { background: rgba(255, 255, 255, .2); }
.gh-pill svg { width: 16px; height: 16px; fill: currentColor; }
.gh-pill .count { padding-left: 8px; border-left: 1px solid rgba(255, 255, 255, .25); font-variant-numeric: tabular-nums; }

.nav-toggle { display: none; position: relative; width: 40px; height: 40px; margin-right: -8px; border: 0; background: transparent; cursor: pointer; }
.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  content: ""; position: absolute; left: 11px; width: 18px; height: 1.5px; border-radius: 2px;
  background: #f5f5f7; transition: transform .25s, background .25s;
}
.nav-toggle span { top: 19px; }
.nav-toggle span::before { left: 0; top: -6px; }
.nav-toggle span::after { left: 0; top: 6px; }
.nav.open .nav-toggle span { background: transparent; }
.nav.open .nav-toggle span::before { transform: translateY(6px) rotate(45deg); }
.nav.open .nav-toggle span::after { transform: translateY(-6px) rotate(-45deg); }

/* ---------- 按钮 ---------- */
.cta { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 48px; padding: 0 26px; border-radius: 999px; border: 1px solid transparent;
  font-size: 16px; font-weight: 600; cursor: pointer;
  transition: background .2s, color .2s, border-color .2s;
}
.btn svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: #0077ed; }
.btn-light { border-color: rgba(255, 255, 255, .32); color: #fff; }
.btn-light:hover { background: rgba(255, 255, 255, .08); }

/* ---------- 首屏 ---------- */
.hero { position: relative; padding: calc(var(--nav-h) + 96px) 0 112px; overflow: hidden; background: var(--night); color: #f5f5f7; text-align: center; }
.hero::before {
  content: ""; position: absolute; left: 50%; top: 46%; width: 1400px; height: 900px; transform: translateX(-50%);
  background: radial-gradient(closest-side, rgba(41, 151, 255, .26), transparent); pointer-events: none;
}
.hero .wrap { position: relative; }
.eyebrow { margin: 0 0 18px; font-size: 15px; font-weight: 500; letter-spacing: .02em; color: #86868b; }
.hero h1 { margin: 0 auto 22px; font-size: clamp(2rem, 9.4vw, 5rem); font-weight: 700; line-height: 1.08; letter-spacing: -.025em; }
.hero h1 .grad { background: linear-gradient(92deg, #2997ff 10%, #64d2ff 55%, #30d158 100%); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero-lead { max-width: 32em; margin: 0 auto 36px; font-size: clamp(1.1rem, 2vw, 1.35rem); color: var(--night-muted); }
.hero-shot { max-width: 1100px; margin: 72px auto 0; }
.hero-shot img {
  width: 100%; border-radius: 26px; border: 1px solid var(--night-line);
  box-shadow: 0 40px 120px -20px rgba(41, 151, 255, .35);
}

/* ---------- 通用区块 ---------- */
.section { padding: 128px 0; }
.section.surface { background: var(--surface); }
.section.dark { background: var(--night); color: #f5f5f7; }
.head { max-width: 760px; margin: 0 0 56px; }
.head.center { margin-left: auto; margin-right: auto; text-align: center; }
.kicker { margin: 0 0 12px; font-size: 15px; font-weight: 600; color: var(--blue); }
.dark .kicker { color: var(--blue-bright); }
.title { margin: 0; font-size: clamp(2rem, 4.4vw, 3.3rem); font-weight: 700; line-height: 1.12; letter-spacing: -.025em; }

.grid { display: grid; gap: 20px; }
.cols-3 { grid-template-columns: repeat(3, 1fr); }

/* ---------- 功能 ---------- */
.card {
  padding: 32px; border-radius: var(--radius); background: #fff; border: 1px solid var(--line);
  transition: transform .25s, box-shadow .25s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 18px 40px rgba(0, 0, 0, .08); }
.card h3 { margin: 22px 0 6px; font-size: 20px; letter-spacing: -.01em; }
.card p { margin: 0; font-size: 15.5px; color: var(--muted); }

.ico { display: grid; place-items: center; width: 54px; height: 54px; border-radius: 15px; background: var(--tile); color: var(--blue); }
.ico svg { width: 32px; height: 32px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.ico .f { fill: currentColor; fill-opacity: .16; stroke: none; }
.ico .s { fill: currentColor; stroke: none; }
.ico .k { fill: var(--tile); stroke: none; }
.ico .dim { stroke-opacity: .35; }

/* ---------- 实车 ---------- */
.gallery { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.shot { margin: 0; overflow: hidden; border-radius: var(--radius); border: 1px solid var(--night-line); background: #111113; }
.shot img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.shot figcaption { padding: 22px 26px 26px; font-size: 15px; color: var(--night-muted); }
.shot figcaption b { display: block; margin-bottom: 2px; font-size: 18px; font-weight: 600; color: #fff; }

/* ---------- 适用车型 ---------- */
.specs { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin: 0; }
.spec { padding: 28px 30px 32px; border-radius: var(--radius); background: #fff; }
.spec dt { margin-bottom: 8px; font-size: 14px; color: var(--muted); }
.spec dd { margin: 0; font-size: clamp(1.35rem, 2.3vw, 1.8rem); font-weight: 700; letter-spacing: -.02em; }
.note { margin: 28px 0 0; font-size: 15px; color: var(--muted); }

/* ---------- 常见问题 ---------- */
.faq { max-width: 860px; margin: 0 auto; }
.faq details { border-bottom: 1px solid #d2d2d7; }
.faq summary { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 24px 0; font-size: 18px; font-weight: 600; cursor: pointer; list-style: none; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; flex: none; font-size: 28px; font-weight: 300; line-height: 1; color: var(--muted); transition: transform .25s; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq .a { padding: 0 48px 24px 0; color: var(--muted); }
.faq .a p { margin: 0; }

/* ---------- 结尾 ---------- */
.final { padding: 128px 0; background: var(--night); color: #f5f5f7; text-align: center; }
.final .mark { display: block; width: 84px; height: 84px; margin: 0 auto 28px; }
.final h2 { margin: 0 0 12px; font-size: clamp(2.2rem, 5vw, 3.6rem); letter-spacing: -.025em; }
.final p { margin: 0 0 36px; font-size: clamp(1.05rem, 1.6vw, 1.2rem); color: var(--night-muted); }

/* ---------- 页脚 ---------- */
.footer { padding: 36px 0 44px; background: var(--surface); color: var(--muted); font-size: 12.5px; }
.foot-top { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px 24px; padding-bottom: 20px; margin-bottom: 20px; border-bottom: 1px solid #d2d2d7; }
.foot-brand { display: flex; align-items: center; gap: 8px; font-size: 15px; font-weight: 600; color: var(--ink); }
.foot-brand .mark { width: 22px; height: 22px; }
.foot-links { display: flex; flex-wrap: wrap; gap: 8px 24px; font-size: 13.5px; }
.foot-links a:hover { color: var(--ink); }
.fine { margin: 0 0 6px; line-height: 1.6; }
.fine a { color: var(--ink); }
.fine a:hover { text-decoration: underline; }

/* ---------- 子页面头部 ---------- */
.page-hero { position: relative; padding: calc(var(--nav-h) + 80px) 0 80px; overflow: hidden; background: var(--night); color: #f5f5f7; }
.page-hero::before {
  content: ""; position: absolute; right: -240px; top: -260px; width: 1000px; height: 760px;
  background: radial-gradient(closest-side, rgba(41, 151, 255, .26), transparent); pointer-events: none;
}
.page-hero .wrap { position: relative; }
.page-hero .kicker { color: var(--blue-bright); }
.page-hero h1 { margin: 0 0 16px; font-size: clamp(2.4rem, 6vw, 4rem); line-height: 1.1; letter-spacing: -.025em; }
.page-lead { max-width: 40em; margin: 0 0 32px; font-size: clamp(1.05rem, 1.8vw, 1.25rem); color: var(--night-muted); }
.cta.left { justify-content: flex-start; }

/* ---------- 安装教程 ---------- */
.doc { display: grid; grid-template-columns: 200px minmax(0, 1fr); gap: 72px; padding-top: 72px; padding-bottom: 120px; }
.toc { position: sticky; top: calc(var(--nav-h) + 32px); align-self: start; }
.toc-title { margin: 0 0 12px; font-size: 13px; font-weight: 600; color: var(--muted); }
.toc ol { margin: 0; padding: 0; list-style: none; border-left: 1px solid var(--line); }
.toc li.gap { margin-top: 16px; }
.toc a { display: block; margin-left: -1px; padding: 6px 0 6px 16px; border-left: 2px solid transparent; font-size: 14.5px; color: var(--muted); transition: color .2s, border-color .2s; }
.toc a:hover { color: var(--ink); }
.toc a.active { border-left-color: var(--blue); color: var(--blue); font-weight: 600; }

.doc-body { min-width: 0; max-width: 760px; font-size: 16px; }
.doc-body code.long { white-space: normal; word-break: break-all; }
.doc-sec { margin-bottom: 56px; padding-bottom: 56px; border-bottom: 1px solid var(--line); }
.doc-sec:last-child { margin-bottom: 0; padding-bottom: 0; border-bottom: 0; }
.doc-sec h2 { margin: 0 0 20px; font-size: clamp(1.6rem, 3vw, 2.1rem); letter-spacing: -.02em; }
.doc-sec p { margin: 0 0 16px; }
.doc-sec a:not(.btn):not(.pill-link) { color: var(--blue); }
.doc-sec a:not(.btn):not(.pill-link):hover { text-decoration: underline; }
.step-no { margin: 0 0 8px !important; font-size: 14px; font-weight: 600; color: var(--blue); }
.muted { color: var(--muted); font-size: 15px; }

.sub-steps { margin: 0 0 20px; padding: 0; list-style: none; counter-reset: sub; }
.sub-steps > li { position: relative; margin-bottom: 14px; padding-left: 40px; counter-increment: sub; }
.sub-steps > li::before {
  content: counter(sub); position: absolute; left: 0; top: 1px; display: grid; place-items: center;
  width: 26px; height: 26px; border-radius: 50%; background: var(--surface); font-size: 13px; font-weight: 700;
}
.dots, .checklist { margin: 0 0 20px; padding: 0; list-style: none; }
.dots li, .checklist li { position: relative; margin-bottom: 10px; padding-left: 30px; }
.dots li::before { content: ""; position: absolute; left: 8px; top: .72em; width: 6px; height: 6px; border-radius: 50%; background: var(--blue); }
.checklist li::before {
  content: ""; position: absolute; left: 0; top: 4px; width: 20px; height: 20px; border-radius: 50%;
  background: var(--blue) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E") center / 12px no-repeat;
}

.path { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin: 10px 0 16px !important; font-family: var(--mono); font-size: 13.5px; }
.path span { padding: 4px 10px; border-radius: 8px; background: var(--surface); }
.path i { font-style: normal; color: var(--muted); }

pre { margin: 0 0 20px; padding: 18px 20px; overflow-x: auto; border-radius: 14px; background: #1d1d1f; color: #f5f5f7; font-family: var(--mono); font-size: 13.5px; line-height: 1.7; }
pre code { padding: 0; background: none; font-size: inherit; white-space: pre; color: inherit; }
pre .c { color: #8e8e93; }

.callout { margin: 0 0 16px; padding: 18px 22px; border-radius: 14px; background: var(--surface); }
.callout b { display: block; margin-bottom: 4px; }
.doc-sec .callout p { margin: 0; font-size: 15px; color: var(--muted); }
.callout.warn { background: #fff4e5; }
.callout.warn b { color: #8a4b00; }
.doc-sec .callout.warn p { color: #7a4a10; }
.callout.tip { background: #eef5ff; }

.pill-link {
  display: inline-block; margin-left: 8px; padding: 1px 12px; border-radius: 999px;
  background: var(--blue); color: #fff; font-size: 13.5px; font-weight: 600; vertical-align: 1px;
}
.pill-link:hover { background: #0077ed; }

.options { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 0 0 24px; }
.option { position: relative; padding: 20px 22px; border: 1px solid var(--line); border-radius: 16px; }
.option.rec { border-color: var(--blue); box-shadow: inset 0 0 0 1px var(--blue); }
.option code { padding: 0; background: none; font-size: 14.5px; font-weight: 700; color: var(--ink); }
.option p { margin: 6px 0 0; font-size: 14.5px; color: var(--muted); }
.option .tag { position: absolute; top: 19px; right: 20px; font-size: 12.5px; font-weight: 600; color: var(--blue); }

.results { margin: 0 0 20px; padding: 0; list-style: none; }
.results li { display: grid; grid-template-columns: 172px 1fr; gap: 16px; align-items: baseline; padding: 14px 0; border-top: 1px solid var(--line); }
.results li:last-child { border-bottom: 1px solid var(--line); }
.results code { justify-self: start; }
code.ok { background: rgba(48, 209, 88, .15); color: #1a7f37; }
code.bad { background: rgba(255, 59, 48, .1); color: #c4291d; }

.more-box { margin-top: 8px; border: 1px solid var(--line); border-radius: 16px; }
.more-box summary { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 18px 22px; font-weight: 600; cursor: pointer; list-style: none; }
.more-box summary::-webkit-details-marker { display: none; }
.more-box summary::after { content: "+"; flex: none; font-size: 26px; font-weight: 300; line-height: 1; color: var(--muted); transition: transform .25s; }
.more-box[open] summary::after { transform: rotate(45deg); }
.more-box > div { padding: 0 22px 6px; }

.qa { margin: 0 0 24px; }
.qa dt { margin-top: 18px; font-weight: 600; }
.qa dt:first-child { margin-top: 0; }
.qa dd { margin: 4px 0 0; color: var(--muted); }

/* ---------- 敬请期待 ---------- */
body.is-dark { background: var(--night); }
.soon { position: relative; display: grid; place-items: center; min-height: 100vh; min-height: 100svh; padding: var(--nav-h) 24px 0; overflow: hidden; background: var(--night); color: #f5f5f7; text-align: center; }
.soon::before {
  content: ""; position: absolute; left: 50%; top: 50%; width: 1100px; height: 800px; transform: translate(-50%, -50%);
  background: radial-gradient(closest-side, rgba(41, 151, 255, .22), transparent); pointer-events: none;
}
.soon-inner { position: relative; }
.soon .mark { display: block; width: 96px; height: 96px; margin: 0 auto 32px; }
.soon .kicker { color: var(--blue-bright); font-size: 17px; }
.soon h1 {
  margin: 0 0 44px; font-size: clamp(3rem, 11vw, 6.5rem); line-height: 1.05; letter-spacing: -.03em;
  background: linear-gradient(180deg, #fff 30%, #8e8e93); -webkit-background-clip: text; background-clip: text; color: transparent;
}

/* ---------- 404 ---------- */
.notfound { display: grid; place-items: center; min-height: 100vh; padding: var(--nav-h) 24px 0; background: var(--night); color: #f5f5f7; text-align: center; }
.notfound h1 { margin: 0 0 8px; font-size: clamp(4rem, 12vw, 7rem); letter-spacing: -.04em; }
.notfound p { margin: 0 0 32px; color: var(--night-muted); }

/* ---------- 滚动渐显 ---------- */
.js .reveal { opacity: 0; transform: translateY(24px); transition: opacity .8s ease, transform .8s ease; }
.js .reveal.in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 1060px) {
  .specs { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 860px) {
  .nav-toggle { display: block; }
  .nav-links {
    display: none; position: absolute; top: var(--nav-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0; padding: 8px 24px 24px;
    background: rgba(0, 0, 0, .94); border-bottom: 1px solid rgba(255, 255, 255, .08);
    font-size: 17px;
  }
  .nav.open .nav-links { display: flex; }
  .nav-links a { padding: 14px 0; border-bottom: 1px solid rgba(255, 255, 255, .08); }
  .nav-links .gh-pill { align-self: flex-start; height: 40px; margin-top: 18px; padding: 0 18px; border-bottom: 0; font-size: 15px; }
  .cols-3 { grid-template-columns: repeat(2, 1fr); }

  .doc { grid-template-columns: minmax(0, 1fr); gap: 40px; padding-top: 40px; }
  .toc { position: static; padding: 20px 22px; border-radius: 16px; background: var(--surface); }
  .toc ol { display: grid; grid-template-columns: 1fr 1fr; gap: 0 16px; border-left: 0; }
  .toc li.gap { margin-top: 0; }
  .toc a { margin-left: 0; padding: 6px 0; border-left: 0; }
}

@media (max-width: 760px) {
  .wrap { padding: 0 16px; }
  .section, .final { padding: 88px 0; }
  .hero { padding: calc(var(--nav-h) + 64px) 0 80px; }
  .hero-shot { margin-top: 52px; }
  .hero-shot img { border-radius: 16px; }
  .head { margin-bottom: 40px; }
  .cols-3, .gallery { grid-template-columns: 1fr; }
  .grid { gap: 14px; }
  .card { display: grid; grid-template-columns: 54px 1fr; column-gap: 18px; align-items: start; padding: 22px; }
  .card .ico { grid-row: span 2; }
  .card h3 { margin: 2px 0 4px; font-size: 18px; }
  .card p { font-size: 15px; }
  .specs { grid-template-columns: 1fr; gap: 12px; }
  .spec { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; padding: 18px 22px; }
  .spec dt { margin: 0; font-size: 15px; }
  .spec dd { font-size: 19px; text-align: right; }
  .faq summary { font-size: 17px; padding: 20px 0; }
  .faq .a { padding-right: 0; }

  .page-hero { padding: calc(var(--nav-h) + 56px) 0 56px; }
  .doc { padding-bottom: 88px; }
  .doc-sec { margin-bottom: 44px; padding-bottom: 44px; }
  .options { grid-template-columns: 1fr; }
  .results li { grid-template-columns: 1fr; gap: 6px; }
  pre { margin-left: -16px; margin-right: -16px; border-radius: 0; font-size: 12.5px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .card, .btn, .faq summary::after { transition: none; }
  .card:hover { transform: none; }
}