/* 24Test 品牌官网 · 共享样式
   布局概念：一条从「检测」到「采购」「接入」「审计」再回到「检测」的闭环，
   每个产品有自己的色相，首页用环形图把四站串起来，产品页用同色带延续。 */

:root {
  /* 色彩 */
  --bg: #f6f8fb;
  --bg-elev: #ffffff;
  --bg-sunk: #eef2f7;
  --fg: #0e1b2e;
  --fg-muted: #4f5f78;
  --line: #d9e0ea;
  --line-strong: #b9c5d6;
  --accent: #2457c5;
  --accent-strong: #1a46a6;
  --on-accent: #ffffff;
  --exam: #2457c5;
  --audit: #1f7a5c;
  --router: #b9561f;
  --tbuy: #6b4fd8;
  --ok: #1f7a5c;
  --warn: #b9770f;
  --info: #2457c5;
  --neutral: #5c6b82;
  --shadow: 0 1px 2px rgb(14 27 46 / .06), 0 8px 24px -12px rgb(14 27 46 / .18);
  /* 字体 */
  --font-sans: 'Public Sans', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Segoe UI', sans-serif;
  --font-mono: ui-monospace, 'SF Mono', Menlo, Consolas, 'Liberation Mono', monospace;
  /* 尺度 */
  --radius: 10px;
  --radius-sm: 6px;
  --wrap: 1120px;
  --gutter-l: max(16px, env(safe-area-inset-left, 0px));
  --gutter-r: max(16px, env(safe-area-inset-right, 0px));
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0a0f1a; --bg-elev: #111a2b; --bg-sunk: #0d1524;
    --fg: #e8edf5; --fg-muted: #9fb0c8; --line: #223049; --line-strong: #34486b;
    --accent: #3d7bff; --accent-strong: #5b8eff; --on-accent: #06101f;
    --exam: #5b8eff; --audit: #3fbf8f; --router: #f0944d; --tbuy: #a78bfa;
    --ok: #3fbf8f; --warn: #f0b64d; --info: #5b8eff; --neutral: #8a9bb5;
    --shadow: 0 1px 2px rgb(0 0 0 / .4), 0 8px 24px -12px rgb(0 0 0 / .6);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0a0f1a; --bg-elev: #111a2b; --bg-sunk: #0d1524;
  --fg: #e8edf5; --fg-muted: #9fb0c8; --line: #223049; --line-strong: #34486b;
  --accent: #3d7bff; --accent-strong: #5b8eff; --on-accent: #06101f;
  --exam: #5b8eff; --audit: #3fbf8f; --router: #f0944d; --tbuy: #a78bfa;
  --ok: #3fbf8f; --warn: #f0b64d; --info: #5b8eff; --neutral: #8a9bb5;
  --shadow: 0 1px 2px rgb(0 0 0 / .4), 0 8px 24px -12px rgb(0 0 0 / .6);
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 84px; -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font-family: var(--font-sans); font-size: 16px; line-height: 1.7;
  -webkit-font-smoothing: antialiased; overflow-x: hidden;
}
img, svg { max-width: 100%; height: auto; }
a { color: var(--accent); text-underline-offset: .18em; }
a:hover { color: var(--accent-strong); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -.01em; margin: 0; text-wrap: balance; }
h1 { font-size: clamp(2rem, 1.2rem + 3.2vw, 3.4rem); font-weight: 800; }
h2 { font-size: clamp(1.5rem, 1.1rem + 1.6vw, 2.25rem); font-weight: 800; }
h3 { font-size: 1.25rem; font-weight: 700; }
h4 { font-size: 1rem; font-weight: 700; }
p { margin: 0; }
p + p { margin-top: .9em; }
ul, ol { margin: 0; padding-left: 1.3em; }
code, kbd, .mono { font-family: var(--font-mono); font-size: .92em; }
code { background: var(--bg-sunk); border: 1px solid var(--line); border-radius: 4px; padding: .1em .4em; }
pre { margin: 0; background: var(--bg-sunk); border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 14px 16px; overflow-x: auto; font-size: .9rem; line-height: 1.55; }
pre code { background: none; border: 0; padding: 0; font-size: inherit; }
table { border-collapse: collapse; width: 100%; font-size: .95rem; }
th, td { text-align: left; vertical-align: top; padding: 10px 12px; border-bottom: 1px solid var(--line); }
th { font-weight: 700; color: var(--fg-muted); font-size: .82rem; letter-spacing: .04em; text-transform: uppercase; }
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: var(--bg-elev); }
.table-wrap table th, .table-wrap table td { white-space: nowrap; }
.table-wrap table td.wrap-cell { white-space: normal; min-width: 18rem; }
.skip { position: absolute; left: -999px; top: 8px; background: var(--accent); color: var(--on-accent); padding: 8px 12px; border-radius: 6px; z-index: 100; }
.skip:focus { left: 12px; }

/* 容器与节奏 */
.wrap { max-width: var(--wrap); margin-inline: auto; padding-left: var(--gutter-l); padding-right: var(--gutter-r); }
.section { padding-block: clamp(48px, 7vw, 96px); }
.section + .section { border-top: 1px solid var(--line); }
.section-head { display: flex; flex-direction: column; gap: 10px; max-width: 46rem; margin-bottom: clamp(24px, 4vw, 40px); }
.eyebrow { font-size: .78rem; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
.eyebrow.exam { color: var(--exam); } .eyebrow.audit { color: var(--audit); } .eyebrow.router { color: var(--router); } .eyebrow.tbuy { color: var(--tbuy); }
.lede { color: var(--fg-muted); font-size: 1.08rem; max-width: 42rem; }
.muted { color: var(--fg-muted); }
.small { font-size: .88rem; }
.stack { display: flex; flex-direction: column; gap: 12px; }
.row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }

/* 顶栏 */
.site-nav { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 50; background: color-mix(in srgb, var(--bg) 88%, transparent); backdrop-filter: blur(12px); border-bottom: 1px solid var(--line); }
.site-nav .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--fg); text-decoration: none; font-weight: 800; letter-spacing: -.01em; font-size: 1.05rem; }
.brand .mark { width: 28px; height: 28px; flex: none; }
.brand .sub { font-weight: 500; color: var(--fg-muted); font-size: .85rem; margin-left: 2px; }
.nav-links { display: flex; align-items: center; gap: 4px; list-style: none; margin: 0; padding: 0; }
.nav-links a { color: var(--fg-muted); text-decoration: none; font-weight: 600; font-size: .92rem; padding: 8px 10px; border-radius: 6px; }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: var(--fg); background: var(--bg-sunk); }
.nav-cta { display: inline-flex; align-items: center; gap: 6px; background: var(--accent); color: var(--on-accent) !important; padding: 8px 14px !important; border-radius: 8px; }
.nav-cta:hover { background: var(--accent-strong); }
.menu-btn { display: none; background: none; border: 1px solid var(--line); color: var(--fg); border-radius: 8px; padding: 8px 12px; font: inherit; font-weight: 600; cursor: pointer; }
@media (max-width: 860px) {
  .menu-btn { display: inline-block; }
  .nav-links { display: none; position: absolute; left: 0; right: 0; top: 100%; flex-direction: column; align-items: stretch; background: var(--bg-elev); border-bottom: 1px solid var(--line); padding: 8px var(--gutter-r) 12px var(--gutter-l); box-shadow: var(--shadow); }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 10px; }
}

/* 按钮 */
.btn { display: inline-flex; align-items: center; gap: 8px; font-weight: 700; font-size: .95rem; text-decoration: none; border-radius: 8px; padding: 11px 18px; border: 1px solid transparent; cursor: pointer; font-family: inherit; line-height: 1.2; }
.btn.primary { background: var(--accent); color: var(--on-accent); }
.btn.primary:hover { background: var(--accent-strong); color: var(--on-accent); }
.btn.ghost { background: transparent; color: var(--fg); border-color: var(--line-strong); }
.btn.ghost:hover { background: var(--bg-sunk); }
.btn.exam { background: var(--exam); color: #fff; } .btn.audit { background: var(--audit); color: #fff; } .btn.router { background: var(--router); color: #fff; }
.btn.exam:hover, .btn.audit:hover, .btn.router:hover { filter: brightness(1.08); color: #fff; }
.btn .arrow { transition: transform .15s ease; }
.btn:hover .arrow { transform: translateX(2px); }

/* 芯片、徽标 */
.chip { display: inline-flex; align-items: center; gap: 6px; font-family: var(--font-mono); font-size: .82rem; padding: 3px 9px; border-radius: 999px; border: 1px solid var(--line-strong); background: var(--bg-elev); color: var(--fg); white-space: nowrap; }
.chip.exam { border-color: color-mix(in srgb, var(--exam) 45%, transparent); color: var(--exam); }
.chip.audit { border-color: color-mix(in srgb, var(--audit) 45%, transparent); color: var(--audit); }
.chip.router { border-color: color-mix(in srgb, var(--router) 45%, transparent); color: var(--router); }
.chip.tbuy { border-color: color-mix(in srgb, var(--tbuy) 45%, transparent); color: var(--tbuy); }
.pill { display: inline-flex; align-items: center; gap: 6px; font-size: .76rem; font-weight: 700; letter-spacing: .04em; padding: 2px 9px; border-radius: 999px; background: var(--bg-sunk); color: var(--fg-muted); white-space: nowrap; }
.pill::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: currentColor; }
.pill.ok { color: var(--ok); background: color-mix(in srgb, var(--ok) 12%, transparent); }
.pill.warn { color: var(--warn); background: color-mix(in srgb, var(--warn) 14%, transparent); }
.pill.info { color: var(--info); background: color-mix(in srgb, var(--info) 12%, transparent); }
.pill.neutral { color: var(--neutral); }

/* 首屏 */
.hero { padding-block: clamp(40px, 7vw, 88px) clamp(32px, 5vw, 64px); position: relative; overflow: hidden; }
.hero::before { content: ""; position: absolute; inset: 0; pointer-events: none; background:
  radial-gradient(60% 50% at 85% 0%, color-mix(in srgb, var(--exam) 16%, transparent), transparent 70%),
  radial-gradient(40% 40% at 10% 100%, color-mix(in srgb, var(--audit) 10%, transparent), transparent 70%); }
.hero .wrap { position: relative; display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(24px, 5vw, 64px); align-items: center; }
.hero-copy { display: flex; flex-direction: column; gap: 18px; min-width: 0; }
.hero-copy .lede { font-size: clamp(1rem, .95rem + .4vw, 1.2rem); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 6px; }
.hero-domains { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 4px; }
.hero-visual { min-width: 0; }
@media (max-width: 900px) { .hero .wrap { grid-template-columns: 1fr; } }

/* 闭环图 */
.loop-figure { margin: 0; display: flex; flex-direction: column; gap: 12px; }
.loop-figure figcaption { color: var(--fg-muted); font-size: .88rem; }
.loop { width: 100%; max-width: 560px; margin-inline: auto; display: block; }
.loop text { font-family: var(--font-sans); }
.loop .ring { fill: none; stroke: var(--line-strong); stroke-width: 1.5; stroke-dasharray: 4 6; }
.loop .arc { fill: none; stroke-width: 10; stroke-linecap: round; opacity: .9; }
.loop .arc.exam { stroke: var(--exam); } .loop .arc.tbuy { stroke: var(--tbuy); } .loop .arc.router { stroke: var(--router); } .loop .arc.audit { stroke: var(--audit); }
.loop .node { fill: var(--bg-elev); stroke-width: 2; }
.loop .node.exam { stroke: var(--exam); } .loop .node.tbuy { stroke: var(--tbuy); } .loop .node.router { stroke: var(--router); } .loop .node.audit { stroke: var(--audit); }
.loop .label { font-size: 15px; font-weight: 800; fill: var(--fg); }
.loop .sub { font-size: 11px; fill: var(--fg-muted); font-family: var(--font-mono); }
.loop .edge { font-size: 11px; fill: var(--fg-muted); }
.loop .center { font-size: 13px; fill: var(--fg-muted); }
.loop .center-title { font-size: 20px; font-weight: 800; fill: var(--fg); }
.loop .arrow { fill: var(--fg-muted); }

/* 产品卡 */
.products { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.product { display: flex; flex-direction: column; gap: 14px; background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; min-width: 0; box-shadow: var(--shadow); position: relative; }
.product::before { content: ""; position: absolute; left: 22px; right: 22px; top: 0; height: 3px; border-radius: 0 0 3px 3px; background: var(--accent); }
.product.exam::before { background: var(--exam); } .product.audit::before { background: var(--audit); } .product.router::before { background: var(--router); }
.product .head { display: flex; align-items: center; justify-content: space-between; gap: 10px; flex-wrap: wrap; }
.product h3 { font-size: 1.2rem; }
.product .name-zh { color: var(--fg-muted); font-weight: 600; font-size: .95rem; }
.product .headline { font-size: 1.05rem; font-weight: 700; }
.product .body { color: var(--fg-muted); font-size: .95rem; }
.product .meta { display: flex; flex-direction: column; gap: 6px; font-size: .88rem; color: var(--fg-muted); border-top: 1px solid var(--line); padding-top: 12px; margin-top: auto; }
.product .meta b { color: var(--fg); font-weight: 600; }
.product .actions { display: flex; flex-wrap: wrap; gap: 10px; }
@media (max-width: 960px) { .products { grid-template-columns: 1fr; } }

/* 闭环步骤 */
.steps { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; counter-reset: step; }
.step { display: grid; grid-template-columns: 44px 1fr; gap: 14px; background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; min-width: 0; }
.step .num { width: 44px; height: 44px; border-radius: 10px; display: grid; place-items: center; font-weight: 800; font-family: var(--font-mono); color: #fff; }
.step.exam .num { background: var(--exam); } .step.tbuy .num { background: var(--tbuy); } .step.router .num { background: var(--router); } .step.audit .num { background: var(--audit); }
.step .title { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; font-weight: 700; }
.step .desc { color: var(--fg-muted); font-size: .95rem; margin-top: 4px; }
.step .flow { margin-top: 10px; font-size: .88rem; color: var(--fg-muted); display: flex; flex-direction: column; gap: 4px; }
.step .flow b { color: var(--fg); font-weight: 600; }
@media (max-width: 760px) { .steps { grid-template-columns: 1fr; } }

/* 产品页色带 */
.band { border-top: 1px solid var(--line); }
.band .wrap { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(24px, 5vw, 56px); align-items: start; }
.band.exam { background: color-mix(in srgb, var(--exam) 6%, var(--bg)); }
.band.audit { background: color-mix(in srgb, var(--audit) 7%, var(--bg)); }
.band.router { background: color-mix(in srgb, var(--router) 7%, var(--bg)); }
@media (max-width: 860px) { .band .wrap { grid-template-columns: 1fr; } }

/* 列表卡 */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 14px; }
.card { background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px; min-width: 0; display: flex; flex-direction: column; gap: 8px; }
.card h4 { font-size: 1rem; }
.card p, .card li { color: var(--fg-muted); font-size: .93rem; }
.card ul { padding-left: 1.1em; display: flex; flex-direction: column; gap: 4px; }
.facts { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 0; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: var(--bg-elev); }
.fact { padding: 16px 18px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); display: flex; flex-direction: column; gap: 4px; min-width: 0; }
.fact .k { font-size: .78rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--fg-muted); }
.fact .v { font-weight: 700; font-size: 1rem; overflow-wrap: anywhere; }
.fact .v.mono { font-family: var(--font-mono); font-weight: 600; font-size: .95rem; }

/* 定义列表 */
.dl { display: grid; grid-template-columns: 11rem 1fr; gap: 8px 18px; margin: 0; }
.dl dt { font-weight: 700; color: var(--fg); }
.dl dd { margin: 0; color: var(--fg-muted); min-width: 0; }
@media (max-width: 640px) { .dl { grid-template-columns: 1fr; gap: 2px 0; } .dl dd { margin-bottom: 10px; } }

/* 路线图 */
.phases { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; }
.phase { background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; display: flex; flex-direction: column; gap: 12px; min-width: 0; }
.phase .when { font-family: var(--font-mono); font-size: .8rem; color: var(--fg-muted); }
.phase ul { list-style: none; padding: 0; display: flex; flex-direction: column; gap: 10px; }
.phase li { display: grid; grid-template-columns: 8px 1fr; gap: 10px; font-size: .93rem; }
.phase li::before { content: ""; width: 8px; height: 8px; border-radius: 50%; margin-top: .55em; background: var(--neutral); }
.phase li.exam::before { background: var(--exam); } .phase li.audit::before { background: var(--audit); } .phase li.router::before { background: var(--router); } .phase li.tbuy::before { background: var(--tbuy); } .phase li.brand::before { background: var(--accent); }
.phase li .tag { color: var(--fg-muted); font-size: .8rem; }
@media (max-width: 900px) { .phases { grid-template-columns: 1fr; } }

/* 信任与品牌关系 */
.trust { background: var(--bg-sunk); border: 1px solid var(--line); border-radius: var(--radius); padding: clamp(20px, 3vw, 32px); display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.trust h3 { font-size: 1.1rem; }
.trust p, .trust li { color: var(--fg-muted); font-size: .95rem; }
.trust ul { display: flex; flex-direction: column; gap: 6px; padding-left: 1.1em; }
@media (max-width: 760px) { .trust { grid-template-columns: 1fr; } }
.brands { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 14px; }
.brand-card { border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; background: var(--bg-elev); display: flex; flex-direction: column; gap: 6px; }
.brand-card .who { font-weight: 800; display: flex; align-items: center; gap: 8px; }
.brand-card .who .dot { width: 10px; height: 10px; border-radius: 50%; background: var(--accent); }
.brand-card.tbuy .who .dot { background: var(--tbuy); }
.brand-card p { color: var(--fg-muted); font-size: .92rem; }

/* FAQ */
.faq { display: flex; flex-direction: column; gap: 0; border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary { cursor: pointer; padding: 14px 0; font-weight: 700; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--fg-muted); font-weight: 400; }
.faq details[open] summary::after { content: "–"; }
.faq .a { padding: 0 0 16px; color: var(--fg-muted); font-size: .95rem; max-width: 46rem; }

/* 页脚 */
.site-footer { border-top: 1px solid var(--line); padding-block: 32px 40px; color: var(--fg-muted); font-size: .88rem; }
.site-footer .wrap { display: grid; grid-template-columns: 1.2fr 1fr 1fr 1fr; gap: 24px; }
.site-footer h4 { font-size: .8rem; letter-spacing: .08em; text-transform: uppercase; color: var(--fg); margin-bottom: 8px; }
.site-footer ul { list-style: none; padding: 0; display: flex; flex-direction: column; gap: 6px; }
.site-footer a { color: var(--fg-muted); text-decoration: none; }
.site-footer a:hover { color: var(--fg); text-decoration: underline; }
.site-footer .legal { grid-column: 1 / -1; border-top: 1px solid var(--line); padding-top: 14px; font-size: .82rem; }
@media (max-width: 860px) { .site-footer .wrap { grid-template-columns: 1fr 1fr; } }
@media (max-width: 520px) { .site-footer .wrap { grid-template-columns: 1fr; } }

/* 页面头（产品页） */
.page-head { padding-block: clamp(36px, 6vw, 72px) clamp(24px, 4vw, 48px); }
.page-head .wrap { display: grid; grid-template-columns: 1.1fr .9fr; gap: clamp(24px, 5vw, 56px); align-items: end; }
.page-head .copy { display: flex; flex-direction: column; gap: 14px; min-width: 0; }
.page-head .aside { display: flex; flex-direction: column; gap: 10px; min-width: 0; }
@media (max-width: 860px) { .page-head .wrap { grid-template-columns: 1fr; } }

/* 复制按钮 */
.copy-btn { font: inherit; font-size: .8rem; font-weight: 600; border: 1px solid var(--line-strong); background: var(--bg-elev); color: var(--fg); border-radius: 6px; padding: 4px 9px; cursor: pointer; }
.copy-btn:hover { background: var(--bg-sunk); }

/* 状态标签表 */
.status-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 10px; }
.status-item { display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: start; padding: 12px 14px; border: 1px solid var(--line); border-radius: var(--radius-sm); background: var(--bg-elev); font-size: .93rem; min-width: 0; }
.status-item .what { min-width: 0; }
.status-item .what small { display: block; color: var(--fg-muted); font-size: .82rem; }

@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { transition: none !important; animation: none !important; } }
@media print { .site-nav, .menu-btn, .hero-actions, .copy-btn { display: none !important; } .section { padding-block: 24px; } }