:root {
  --ink: #2b2523;
  --muted: #6f6763;
  --paper: #f7f4f1;
  --white: #ffffff;
  --line: #e2dbd6;
  --brand-red: #85272b;
  --brand-red-dark: #64191d;
  --charcoal: #2b2523;
  --accent: #ad7774;
  --max: 1180px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  line-height: 1.7;
}

a { color: inherit; }

.site-header {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  padding: 0 4vw;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, .96);
  position: sticky;
  top: 0;
  z-index: 20;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  text-decoration: none;
}

.brand-mark {
  width: 42px;
  height: 40px;
  object-fit: contain;
  flex: 0 0 auto;
}

.brand-name { display: grid; line-height: 1.2; }
.brand-name small { margin-top: 3px; color: var(--brand-red); font-size: 9px; letter-spacing: .2em; }

nav { display: flex; gap: 24px; }
nav a { color: var(--muted); text-decoration: none; font-size: 14px; }
nav a:hover { color: var(--ink); }

.intro {
  min-height: min(720px, 82vh);
  display: flex;
  align-items: center;
  background:
    linear-gradient(90deg, rgba(35, 27, 25, .97), rgba(53, 31, 30, .84) 58%, rgba(100, 25, 29, .34)),
    url("assets/hero-black-walnut.jpg") center 52% / cover;
  color: var(--white);
}

.intro-inner {
  width: min(var(--max), 92vw);
  margin: 0 auto;
  padding: 76px 0;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
}

.hero-logo {
  width: 76px;
  height: 86px;
  margin-bottom: 22px;
  object-fit: cover;
  border: 1px solid rgba(255,255,255,.28);
}

h1, h2, h3, p { letter-spacing: 0; }
h1 { margin: 0; max-width: 760px; font-size: clamp(46px, 7vw, 88px); line-height: 1.08; }
h2 { margin: 0; font-size: clamp(30px, 4vw, 48px); line-height: 1.2; }
h3 { font-size: 20px; }

.lead {
  max-width: 720px;
  margin: 28px 0 0;
  font-size: 21px;
  color: rgba(255,255,255,.86);
}

.intro-actions, .visit-actions { display: flex; flex-wrap: wrap; gap: 16px; margin-top: 34px; }
.primary-action, .secondary-action {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 22px;
  text-decoration: none;
  font-weight: 700;
}
.primary-action { background: var(--brand-red); color: var(--white); }
.primary-action:hover { background: var(--brand-red-dark); }
.secondary-action { border: 1px solid currentColor; }
.text-action { display: inline-flex; align-items: center; color: rgba(255,255,255,.85); }

.quick-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  max-width: 920px;
  margin: 62px 0 0;
  background: rgba(255,255,255,.22);
}
.quick-facts div { min-height: 110px; padding: 22px; background: rgba(43, 30, 28, .90); }
dt { color: var(--muted); font-size: 13px; }
.quick-facts dt { color: rgba(255,255,255,.58); }
dd { margin: 4px 0 0; font-weight: 700; }

.section { padding: 90px max(4vw, calc((100vw - var(--max)) / 2)); }
.section-band { background: var(--paper); }
.section-heading { max-width: 760px; margin-bottom: 48px; }
.section-heading > p:last-child { color: var(--muted); }

.facts-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 70px; }
.facts-grid dl { margin: 0; }
.facts-grid dt { margin-top: 22px; }
.facts-grid dd { padding-bottom: 18px; border-bottom: 1px solid var(--line); }

.evidence {
  display: grid;
  grid-template-columns: minmax(220px, 360px) 1fr;
  gap: 42px;
  align-items: center;
  margin: 74px 0 0;
  padding-top: 58px;
  border-top: 1px solid var(--line);
}
.evidence img { width: 100%; max-height: 620px; object-fit: cover; object-position: top; border: 1px solid var(--line); }
.evidence figcaption { display: grid; gap: 10px; }
.evidence figcaption strong { font-size: 26px; }
.evidence figcaption span { color: var(--muted); }

.product-columns { display: grid; grid-template-columns: repeat(3, 1fr); gap: 50px; }
.product-columns ul { margin: 0; padding-left: 20px; color: var(--muted); }

.guide-links { display: grid; grid-template-columns: minmax(260px, .8fr) 1.2fr; gap: 70px; padding: 80px max(4vw, calc((100vw - var(--max)) / 2)); }
.guide-link-list { border-top: 1px solid var(--ink); }
.guide-link-list a { display: grid; grid-template-columns: 42px 1fr; gap: 4px 18px; padding: 22px 0; border-bottom: 1px solid var(--line); text-decoration: none; }
.guide-link-list span { grid-row: 1 / 3; color: var(--brand-red); font-weight: 700; }
.guide-link-list em { color: var(--muted); font-style: normal; font-size: 14px; }

.editorial-hero { padding: 120px max(4vw, calc((100vw - var(--max)) / 2)); color: var(--white); background: linear-gradient(100deg, rgba(35,27,25,.98), rgba(100,25,29,.62)), url("assets/hero-black-walnut.jpg") center / cover; }
.editorial-hero h1 { font-size: clamp(44px, 7vw, 86px); }
.editorial-hero .lead { max-width: 820px; }
.budget-hero { background-position: center, center 65%; }
.article-layout { display: grid; grid-template-columns: 220px minmax(0, 760px); gap: 80px; justify-content: center; align-items: start; }
.article-index { position: sticky; top: 100px; display: grid; gap: 12px; padding-top: 12px; border-top: 1px solid var(--ink); }
.article-index a { color: var(--muted); text-decoration: none; }
.article-body > section { padding: 0 0 72px; margin: 0 0 72px; border-bottom: 1px solid var(--line); }
.article-body p, .article-body li { color: var(--muted); }
.article-body h2 { margin-bottom: 24px; }
.callout { margin: 28px 0; padding: 24px; border-left: 4px solid var(--brand-red); background: var(--paper); }
.callout p { margin-bottom: 0; }
.spec-table { border-top: 1px solid var(--ink); }
.spec-table div { display: flex; justify-content: space-between; gap: 20px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.spec-table span { color: var(--muted); }
.check-list { padding-left: 24px; }
.check-list li { padding: 10px 0; border-bottom: 1px solid var(--line); }
.case-grid { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--ink); border-left: 1px solid var(--line); }
.case-grid article { padding: 24px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.case-grid span, .case-grid p { color: var(--muted); }
.case-grid strong { color: var(--brand-red); font-size: 24px; }
.two-column-info { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; margin-top: 54px; }
.two-column-info div { padding-top: 20px; border-top: 1px solid var(--ink); }
.two-column-info p { color: var(--muted); }

.area-hero {
  min-height: 610px;
  display: flex;
  align-items: center;
  padding: 80px max(4vw, calc((100vw - var(--max)) / 2));
  color: var(--white);
  background:
    linear-gradient(90deg, rgba(35, 27, 25, .98), rgba(53, 31, 30, .84) 60%, rgba(100, 25, 29, .30)),
    url("assets/hero-black-walnut.jpg") center / cover;
}
.area-hero > div { width: min(820px, 100%); }
.area-hero h1 { font-size: clamp(40px, 6vw, 72px); }

.city-grid { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--ink); border-left: 1px solid var(--line); }
.city-grid article { min-height: 220px; padding: 26px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.city-grid h3 { margin-top: 0; color: var(--brand-red); }
.city-grid p { color: var(--muted); }

.service-steps { margin: 0; padding: 0; list-style: none; counter-reset: steps; border-top: 1px solid var(--ink); }
.service-steps li { counter-increment: steps; display: grid; grid-template-columns: 70px minmax(180px, 280px) 1fr; gap: 24px; padding: 24px 0; border-bottom: 1px solid var(--line); }
.service-steps li::before { content: "0" counter(steps); color: var(--brand-red); font-weight: 700; }
.service-steps span { color: var(--muted); }

.price-list { border-top: 1px solid var(--ink); }
.price-list div { display: flex; justify-content: space-between; gap: 30px; padding: 22px 0; border-bottom: 1px solid var(--line); }
.price-list span { color: var(--muted); }

.timeline, .warranty-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--line); }
.timeline div, .warranty-grid div { min-height: 130px; display: grid; align-content: center; gap: 8px; padding: 22px; background: var(--white); }
.timeline strong, .warranty-grid strong { color: var(--brand-red); font-size: 22px; }
.timeline span, .warranty-grid span { color: var(--muted); }
.fine-print { margin: 18px 0 44px; color: var(--muted); font-size: 14px; }

.faq-list { border-top: 1px solid var(--ink); }
details { border-bottom: 1px solid var(--line); }
summary { cursor: pointer; padding: 24px 38px 24px 0; font-weight: 700; }
details p { max-width: 820px; margin: 0 0 26px; color: var(--muted); }

.visit {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  padding: 80px max(4vw, calc((100vw - var(--max)) / 2));
  color: var(--white);
  background: var(--charcoal);
}
.visit p:last-child { max-width: 720px; color: rgba(255,255,255,.75); }
.visit-actions { margin: 0; flex-shrink: 0; }

footer {
  display: flex;
  justify-content: space-between;
  gap: 30px;
  padding: 32px 4vw;
  color: var(--muted);
  font-size: 13px;
}
footer div { display: flex; flex-wrap: wrap; gap: 20px; }
.footer-compliance { width: 100%; }
.footer-compliance a { color: inherit; }
.footer-brand { display: flex; align-items: center; gap: 10px; margin: 0; }
.footer-brand img { width: 38px; height: 36px; object-fit: contain; }

@media (max-width: 760px) {
  .site-header { min-height: 62px; }
  nav { display: none; }
  .intro { min-height: 760px; background-position: center, 58% center; }
  .intro-inner { padding: 64px 0 44px; }
  h1 { font-size: 48px; }
  .lead { font-size: 18px; }
  .quick-facts, .facts-grid, .product-columns, .timeline, .warranty-grid { grid-template-columns: 1fr; }
  .city-grid { grid-template-columns: 1fr; }
  .guide-links, .article-layout, .case-grid, .two-column-info { grid-template-columns: 1fr; }
  .guide-links { gap: 34px; }
  .article-index { position: static; }
  .editorial-hero { padding-top: 90px; padding-bottom: 90px; }
  .editorial-hero h1 { font-size: 42px; }
  .service-steps li { grid-template-columns: 44px 1fr; }
  .service-steps span { grid-column: 2; }
  .area-hero { min-height: 720px; background-position: center, 58% center; }
  .area-hero h1 { font-size: 36px; }
  .quick-facts { margin-top: 42px; }
  .quick-facts div { min-height: 82px; }
  .section { padding-top: 68px; padding-bottom: 68px; }
  .evidence { grid-template-columns: 1fr; }
  .evidence img { max-height: 520px; width: min(100%, 360px); }
  .price-list div { flex-direction: column; gap: 4px; }
  .visit, footer { align-items: flex-start; flex-direction: column; }
}