:root {
  --brand: #B9473F; --amber: #D89A45; --ink: #1E2026; --bg: #F7F4EF; --bg2: #EEE9E2;
  --text: #2B2D31; --muted: #6F706F; --accent: #E06A3B; --line: #D9D3CB; --white: #fff;
  --radius: 18px; --shadow: 0 20px 55px rgba(30,32,38,.09); --max: 1180px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: system-ui,-apple-system,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif; line-height: 1.72; -webkit-font-smoothing: antialiased; }
img { display: block; max-width: 100%; height: auto; border-radius: 16px; }
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 3px; }
button,input { font: inherit; }
button { cursor: pointer; }
.shell { width: min(calc(100% - 40px), var(--max)); margin-inline: auto; }
.narrow { width: min(calc(100% - 40px), 820px); margin-inline: auto; }
.skip-link { position: fixed; left: 16px; top: -80px; z-index: 1000; background: var(--ink); color: white; padding: 10px 14px; border-radius: 0 0 10px 10px; }
.skip-link:focus { top: 0; }
.site-header { position: sticky; top: 0; z-index: 100; background: rgba(247,244,239,.96); backdrop-filter: blur(12px); border-bottom: 1px solid rgba(30,32,38,.08); }
.header-row { min-height: 76px; display: flex; align-items: center; gap: 22px; }
.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; margin-right: auto; }
.brand img { width: 44px; height: 44px; object-fit: contain; border-radius: 12px; }
.brand span { display: grid; line-height: 1.15; }
.brand strong { font-size: 1.08rem; letter-spacing: .03em; }
.brand small { color: var(--muted); font-size: .72rem; margin-top: 4px; }
.main-nav { display: flex; gap: 6px; align-items: center; }
.main-nav a { text-decoration: none; color: #45464a; padding: 8px 10px; border-radius: 10px; font-size: .93rem; }
.main-nav a:hover,.main-nav a[aria-current="page"] { color: var(--brand); background: #fff; }
.search-trigger,.menu-toggle { border: 1px solid var(--line); background: #fff; color: var(--ink); padding: 9px 13px; border-radius: 10px; }
.menu-toggle { display: none; }
.site-main { min-height: 70vh; }
.hero-section { padding: 58px 0 36px; overflow: hidden; }
.hero-grid,.page-hero-grid,.visual-feature-grid,.topic-hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 52px; align-items: center; }
.hero-copy h1,.page-hero h1,.topic-hero h1 { margin: 8px 0 20px; color: var(--ink); font-size: clamp(2.2rem,5vw,4.5rem); line-height: 1.08; letter-spacing: -.035em; }
.page-hero h1,.topic-hero h1 { font-size: clamp(2rem,4vw,3.7rem); }
.hero-lead,.page-hero p,.topic-hero p { font-size: 1.1rem; color: #505156; max-width: 760px; }
.eyebrow { margin: 0 0 8px; color: var(--brand); font-weight: 800; font-size: .78rem; letter-spacing: .13em; text-transform: uppercase; }
.eyebrow.warm { color: #f5c277; }
.action-row { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; margin-top: 28px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 10px 17px; border-radius: 12px; border: 1px solid var(--line); text-decoration: none; font-weight: 750; }
.button.primary { background: var(--brand); color: white; border-color: var(--brand); }
.button.primary:hover { background: #a73d36; }
.button.ghost { background: transparent; color: var(--ink); }
.button.warm { background: var(--amber); border-color: var(--amber); color: #261b12; }
.button.full { width: 100%; margin-top: 10px; }
.hero-points { margin: 28px 0 0; padding: 0; list-style: none; display: grid; gap: 8px; color: var(--muted); }
.hero-points li::before,.check-list li::before { content: "✓"; color: var(--brand); font-weight: 900; margin-right: 8px; }
.hero-media { margin: 0; position: relative; }
.hero-media::before { content: ""; position: absolute; inset: 10% -12% -12% 18%; background: var(--bg2); border-radius: 40px; z-index: -1; }
.hero-media img { box-shadow: var(--shadow); width: 100%; aspect-ratio: 1.22; object-fit: cover; }
.hero-media figcaption { color: var(--muted); font-size: .84rem; margin-top: 10px; }
.section { padding: 72px 0; }
.section.alt-bg { background: var(--bg2); }
.section-heading { display: grid; grid-template-columns: 1.1fr .9fr; gap: 32px; align-items: end; margin-bottom: 30px; }
.section-heading h2,.dark-band h2,.visual-feature h2,.closing-cta h2,.related-panel h2 { margin: 0; color: var(--ink); font-size: clamp(1.65rem,3vw,2.55rem); line-height: 1.18; }
.section-heading > p { margin: 0; color: var(--muted); }
.entry-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 22px; }
.entry-grid.small { grid-template-columns: repeat(3,1fr); }
.entry-card { background: #fff; border: 1px solid rgba(30,32,38,.08); border-radius: var(--radius); overflow: hidden; box-shadow: 0 10px 30px rgba(30,32,38,.04); }
.entry-card > div { padding: 22px; }
.entry-card img { width: 100%; aspect-ratio: 1.75; object-fit: cover; border-radius: 0; }
.entry-card h3 { font-size: 1.28rem; margin: 0 0 8px; line-height: 1.3; }
.entry-card h3 a,.article-feed h3 a,.article-index h2 a,.topic-index h2 a { text-decoration: none; }
.entry-card p,.article-feed p,.article-index p { color: var(--muted); }
.text-link { color: var(--brand); font-weight: 750; }
.dark-band { padding: 76px 0; background: var(--ink); color: #e6e3df; }
.dark-band h2 { color: #fff; }
.dark-band p { color: #bfc0c4; }
.split-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.decision-list { display: grid; gap: 14px; }
.decision-list > div { display: grid; grid-template-columns: 44px 1fr; column-gap: 14px; padding: 18px; border: 1px solid rgba(255,255,255,.12); border-radius: 14px; background: rgba(255,255,255,.035); }
.decision-list span { grid-row: 1 / span 2; color: #f5c277; font-weight: 850; }
.decision-list p { margin: 4px 0 0; }
.editorial-list { border-top: 1px solid var(--line); }
.editorial-list article { display: grid; grid-template-columns: 60px 1fr; gap: 12px; padding: 26px 0; border-bottom: 1px solid var(--line); }
.editorial-list .index { font-size: 1.45rem; color: var(--brand); font-weight: 850; }
.editorial-list h3 { margin: 0 0 6px; font-size: 1.3rem; }
.editorial-list p { margin: 0 0 7px; color: var(--muted); }
.visual-feature { padding: 72px 0; background: #fff; }
.visual-feature figure { margin: 0; }
.visual-feature img { width: 100%; aspect-ratio: 1.46; object-fit: cover; }
.check-list { list-style: none; padding: 0; display: grid; gap: 9px; }
.article-feed { display: grid; grid-template-columns: repeat(3,1fr); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.article-feed article { min-height: 250px; padding: 24px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.article-feed h3 { margin: 12px 0 9px; font-size: 1.24rem; line-height: 1.35; }
.article-meta { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; color: var(--muted); font-size: .82rem; }
.article-meta span { color: var(--brand); font-weight: 800; }
.section-action { margin-top: 28px; text-align: center; }
.section-action.left { text-align: left; }
.topic-strip { display: grid; grid-template-columns: repeat(2,1fr); gap: 20px; }
.topic-strip article { background: #fff; border-radius: var(--radius); overflow: hidden; display: grid; grid-template-columns: 180px 1fr; }
.topic-strip img { height: 100%; width: 100%; object-fit: cover; border-radius: 0; }
.topic-strip div { padding: 22px; }
.topic-strip h3 { margin: 0 0 7px; line-height: 1.3; }
.topic-strip h3 a { text-decoration: none; }
.topic-strip p { color: var(--muted); margin-bottom: 0; }
.faq-list { display: grid; gap: 10px; }
.faq-list details { background: #fff; border: 1px solid var(--line); border-radius: 13px; padding: 16px 18px; }
.faq-list summary { cursor: pointer; font-weight: 760; color: var(--ink); }
.faq-list p { margin: 12px 0 0; color: var(--muted); }
.closing-cta { background: #fff; }
.closing-grid { display: grid; grid-template-columns: 1.2fr .8fr; gap: 32px; align-items: center; }
.closing-grid .action-row { justify-content: flex-end; }
.page-hero,.topic-hero { padding: 56px 0 30px; }
.page-hero.compact { padding-bottom: 10px; }
.page-hero.compact .shell { max-width: 900px; }
.page-hero-grid > img,.topic-hero-grid > img { width: 100%; aspect-ratio: 1.45; object-fit: cover; box-shadow: var(--shadow); }
.breadcrumbs { padding-top: 20px; color: var(--muted); font-size: .86rem; }
.breadcrumbs ol { list-style: none; display: flex; gap: 8px; padding: 0; margin: 0; flex-wrap: wrap; }
.breadcrumbs li:not(:last-child)::after { content: "/"; margin-left: 8px; color: #aaa29a; }
.two-col { display: grid; grid-template-columns: 1.1fr .9fr; gap: 48px; align-items: start; }
.note-box { padding: 24px; border-radius: var(--radius); background: #fff; border-left: 4px solid var(--brand); box-shadow: var(--shadow); }
.note-box > strong { font-size: 1.15rem; }
.note-box ol,.note-box ul { padding-left: 20px; margin-bottom: 0; }
.comparison-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
.comparison-grid article { border: 1px solid rgba(255,255,255,.14); border-radius: var(--radius); padding: 28px; }
.comparison-grid h2 { font-size: 1.5rem; }
.comparison-grid ul { padding-left: 20px; }
.device-grid,.scenario-grid,.principle-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 18px; }
.scenario-grid,.principle-grid { grid-template-columns: repeat(2,1fr); }
.device-grid article,.scenario-grid article,.principle-grid article { padding: 24px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
.device-grid h3,.scenario-grid h3,.principle-grid h2 { margin-top: 0; color: var(--ink); }
.device-grid p,.scenario-grid p,.principle-grid p { color: var(--muted); }
.process-list,.safety-timeline { display: grid; gap: 12px; }
.process-list > div,.safety-timeline article { display: grid; grid-template-columns: 58px 1fr; gap: 18px; padding: 20px; background: #fff; border-radius: 14px; }
.process-list span,.safety-timeline span { font-size: 1.5rem; font-weight: 850; color: var(--brand); }
.process-list h3,.safety-timeline h2 { margin: 0 0 5px; }
.process-list p,.safety-timeline p { margin: 0; color: var(--muted); }
.related-panel { display: grid; grid-template-columns: 1fr auto; gap: 32px; align-items: center; padding: 28px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
.related-panel p { color: var(--muted); margin-bottom: 0; }
.metricless-grid { display: grid; grid-template-columns: repeat(5,1fr); gap: 12px; }
.metricless-grid article { padding: 20px; border-top: 4px solid var(--brand); background: #fff; border-radius: 0 0 14px 14px; }
.metricless-grid strong { color: var(--ink); }
.metricless-grid p { color: var(--muted); font-size: .92rem; margin-bottom: 0; }
.quote-panel,.search-demo { padding: 28px; border: 1px solid rgba(255,255,255,.15); border-radius: var(--radius); background: rgba(255,255,255,.04); }
.quote-panel p { font-size: 1.2rem; color: #ece8e2; margin: 0; }
.content-figure { margin: 0; }
.content-figure img { width: 100%; aspect-ratio: 1.48; object-fit: cover; }
.warning-list { display: grid; grid-template-columns: repeat(2,1fr); gap: 14px; }
.warning-list > div { padding: 20px; border-left: 4px solid var(--accent); background: #fff; }
.warning-list p { color: var(--muted); margin-bottom: 0; }
.three-paths { display: grid; grid-template-columns: repeat(3,1fr); gap: 18px; }
.three-paths article { padding: 26px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); }
.three-paths span { color: var(--brand); font-weight: 900; }
.three-paths h2 { font-size: 1.35rem; }
.three-paths p { color: var(--muted); }
.search-demo .fake-label { color: #f5c277; font-size: .8rem; }
.search-demo strong { display: block; font-size: 1.8rem; color: white; margin: 8px 0; }
.link-stack { display: grid; gap: 12px; }
.link-stack a { display: grid; text-decoration: none; padding: 18px; border-radius: 14px; border: 1px solid rgba(255,255,255,.15); }
.link-stack strong { color: white; }
.link-stack span { color: #bfc0c4; }
.guide-steps,.topic-steps { display: grid; gap: 0; border-top: 1px solid var(--line); }
.guide-steps article,.topic-steps article { display: grid; grid-template-columns: 80px 1fr; gap: 16px; padding: 26px 0; border-bottom: 1px solid var(--line); }
.guide-steps span,.topic-steps span { color: var(--brand); font-size: 1.6rem; font-weight: 900; }
.guide-steps h3,.topic-steps h3 { margin: 0 0 6px; font-size: 1.25rem; }
.guide-steps p,.topic-steps p { margin: 0; color: var(--muted); }
.faq-layout { display: grid; grid-template-columns: 1fr 330px; gap: 32px; align-items: start; }
.faq-list.large details { padding: 20px 22px; }
.faq-aside { position: sticky; top: 100px; padding: 22px; background: var(--bg2); border-radius: var(--radius); }
.faq-aside img { margin-bottom: 18px; }
.article-index { display: grid; gap: 20px; }
.article-index article { display: grid; grid-template-columns: 300px 1fr; gap: 28px; padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.article-index img { width: 100%; height: 100%; max-height: 210px; object-fit: cover; }
.article-index h2 { margin: 10px 0; font-size: 1.5rem; }
.article-header { padding-top: 48px; }
.article-header h1 { margin: 12px 0 16px; color: var(--ink); font-size: clamp(2rem,4.5vw,3.8rem); line-height: 1.12; }
.article-deck { font-size: 1.15rem; color: var(--muted); }
.article-cover { margin-top: 28px; }
.article-cover img { width: 100%; max-height: 510px; object-fit: cover; }
.article-body { padding-top: 38px; }
.article-body section { margin-bottom: 34px; }
.article-body h2 { color: var(--ink); font-size: 1.55rem; }
.article-body p { font-size: 1.06rem; }
.article-note { padding: 20px; border-left: 4px solid var(--amber); background: var(--bg2); border-radius: 0 14px 14px 0; }
.article-note p { margin-bottom: 0; color: var(--muted); }
.related-list { display: grid; gap: 10px; }
.related-list a { display: grid; padding: 18px; border: 1px solid var(--line); border-radius: 14px; text-decoration: none; background: #fff; }
.related-list span { color: var(--muted); font-size: .92rem; }
.topic-index { display: grid; gap: 26px; }
.topic-index article { display: grid; grid-template-columns: .8fr 1.2fr; gap: 28px; padding-bottom: 26px; border-bottom: 1px solid var(--line); }
.topic-index img { width: 100%; height: 100%; max-height: 340px; object-fit: cover; }
.topic-index h2 { font-size: 1.7rem; margin-top: 0; }
.topic-index p { color: var(--muted); }
.topic-intro-short { font-size: .95rem; }
.search-form label { display: block; font-weight: 750; margin-bottom: 8px; }
.search-input-row { display: flex; gap: 8px; }
.search-input-row input { flex: 1; min-width: 0; border: 1px solid var(--line); border-radius: 10px; padding: 12px 14px; background: white; color: var(--ink); }
.search-input-row button { border: 0; border-radius: 10px; background: var(--brand); color: white; padding: 12px 18px; font-weight: 800; }
.search-form.in-page { max-width: 720px; margin-top: 24px; }
.search-results { display: grid; gap: 16px; max-width: 900px; }
.search-results article { padding: 22px; background: #fff; border: 1px solid var(--line); border-radius: 14px; }
.search-results article > span { color: var(--brand); font-weight: 800; font-size: .8rem; }
.search-results h2 { margin: 6px 0; font-size: 1.35rem; }
.search-results p { color: var(--muted); margin-bottom: 0; }
.result-note { color: var(--muted); }
mark { background: #f6dc9f; padding: 0 .08em; }
.empty-state { max-width: 760px; padding: 30px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
.tag-links { display: flex; flex-wrap: wrap; gap: 10px; }
.tag-links a { padding: 8px 12px; border-radius: 999px; background: var(--bg2); text-decoration: none; }
.privacy-sections { display: grid; grid-template-columns: repeat(2,1fr); gap: 18px; }
.privacy-sections section { padding: 24px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); }
.privacy-sections h2 { margin-top: 0; }
.privacy-sections p { color: var(--muted); }
.error-page { padding: 100px 0; text-align: center; }
.error-page h1 { font-size: clamp(2rem,5vw,4rem); color: var(--ink); }
.help-grid { margin-top: 40px; display: grid; grid-template-columns: repeat(3,1fr); gap: 12px; text-align: left; }
.help-grid a { display: grid; padding: 18px; border: 1px solid var(--line); border-radius: 14px; background: #fff; text-decoration: none; }
.help-grid span { color: var(--muted); font-size: .9rem; }
.search-modal[hidden] { display: none !important; }
.search-modal { position: fixed; inset: 0; z-index: 500; display: grid; place-items: start center; padding-top: 10vh; }
.search-backdrop { position: absolute; inset: 0; background: rgba(20,21,25,.72); }
.search-panel { position: relative; width: min(calc(100% - 32px), 680px); background: var(--bg); border-radius: 20px; padding: 32px; box-shadow: 0 30px 100px rgba(0,0,0,.35); }
.search-panel h2 { margin: 0 0 10px; font-size: 1.8rem; }
.search-panel p { color: var(--muted); }
.modal-close { position: absolute; top: 16px; right: 16px; border: 1px solid var(--line); background: white; border-radius: 8px; padding: 6px 10px; }
.modal-open { overflow: hidden; }
.site-footer { background: var(--ink); color: #d5d2cd; padding: 58px 0 18px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr repeat(3,1fr); gap: 36px; }
.footer-grid h2 { color: white; font-size: .95rem; }
.footer-grid a { display: block; color: #c3c0bb; text-decoration: none; margin: 8px 0; }
.footer-grid a:hover { color: white; }
.footer-brand strong { font-size: 1.3rem; color: white; }
.footer-brand p { color: #aaa8a3; max-width: 420px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.1); margin-top: 34px; padding-top: 18px; display: flex; justify-content: space-between; gap: 12px; color: #8f8d89; font-size: .82rem; }
.back-top { position: fixed; right: 18px; bottom: 18px; width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 50%; background: white; color: var(--ink); box-shadow: var(--shadow); opacity: 0; pointer-events: none; transform: translateY(10px); transition: .2s ease; }
.back-top.visible { opacity: 1; pointer-events: auto; transform: none; }
@media (max-width: 1100px) {
  .main-nav { position: absolute; left: 20px; right: 20px; top: 68px; display: none; flex-direction: column; align-items: stretch; padding: 14px; background: #fff; border: 1px solid var(--line); border-radius: 14px; box-shadow: var(--shadow); }
  .main-nav.is-open { display: flex; } .menu-toggle { display: inline-flex; }
  .article-feed { grid-template-columns: repeat(2,1fr); }
  .metricless-grid { grid-template-columns: repeat(3,1fr); }
}
@media (max-width: 820px) {
  .shell,.narrow { width: min(calc(100% - 28px), var(--max)); }
  .hero-grid,.page-hero-grid,.topic-hero-grid,.visual-feature-grid,.split-layout,.two-col,.closing-grid,.faq-layout,.topic-index article { grid-template-columns: 1fr; }
  .hero-media,.page-hero-grid > img,.topic-hero-grid > img { max-width: 680px; }
  .entry-grid,.entry-grid.small,.comparison-grid,.scenario-grid,.principle-grid,.privacy-sections,.warning-list { grid-template-columns: 1fr; }
  .device-grid,.three-paths { grid-template-columns: 1fr; }
  .topic-strip { grid-template-columns: 1fr; }
  .article-index article { grid-template-columns: 220px 1fr; }
  .faq-aside { position: static; }
  .closing-grid .action-row { justify-content: flex-start; }
  .footer-grid { grid-template-columns: repeat(2,1fr); }
  .metricless-grid { grid-template-columns: repeat(2,1fr); }
}
@media (max-width: 600px) {
  .header-row { min-height: 68px; gap: 8px; } .brand small { display: none; } .brand img { width: 38px; height: 38px; }
  .search-trigger { padding-inline: 10px; font-size: .88rem; }
  .hero-section { padding-top: 34px; } .section,.dark-band,.visual-feature { padding: 52px 0; }
  .section-heading { grid-template-columns: 1fr; gap: 10px; }
  .article-feed { grid-template-columns: 1fr; border-left: 0; }
  .article-feed article { border-left: 1px solid var(--line); }
  .topic-strip article { grid-template-columns: 110px 1fr; }
  .article-index article { grid-template-columns: 1fr; }
  .article-index img { max-height: 260px; }
  .metricless-grid { grid-template-columns: 1fr; }
  .related-panel { grid-template-columns: 1fr; }
  .guide-steps article,.topic-steps article { grid-template-columns: 52px 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; }
  .help-grid { grid-template-columns: 1fr; }
  .search-panel { padding: 26px 20px; }
}
@media (max-width: 390px) {
  .header-row { flex-wrap: wrap; padding-block: 8px; } .brand { flex: 1 1 auto; }
  .menu-toggle,.search-trigger { font-size: .82rem; }
  .hero-copy h1,.page-hero h1,.topic-hero h1 { font-size: 2rem; }
  .topic-strip article { grid-template-columns: 1fr; } .topic-strip img { height: 180px; }
  .search-input-row { flex-direction: column; }
}