/* ============================================================
   途营 TUYING · 车载拉丝床垫品牌官网
   设计系统：户外工业 · 高端克制（见 design-system/途营/MASTER.md）
   ============================================================ */
:root {
  --c-primary: #1E293B;
  --c-secondary: #334155;
  --c-cta: #DC2626;
  --c-cta-hover: #B91C1C;
  --c-bg: #F8FAFC;
  --c-text: #0F172A;
  --c-muted: #475569;
  --c-accent: #EA580C;
  --c-line: #E2E8F0;
  --c-card: #FFFFFF;
  --radius: 12px;
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, .08);
  --shadow-md: 0 8px 24px rgba(15, 23, 42, .10);
  --font: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}
body { font-family: var(--font); color: var(--c-text); background: var(--c-bg); line-height: 1.7; font-size: 16px; }
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.container { max-width: 1160px; margin: 0 auto; padding: 0 24px; }

/* ---------- 顶部导航 ---------- */
.nav { position: fixed; top: 0; left: 0; right: 0; z-index: 100; background: rgba(15, 23, 42, .92); backdrop-filter: blur(8px); border-bottom: 1px solid rgba(255,255,255,.08); }
.nav-inner { max-width: 1160px; margin: 0 auto; padding: 0 24px; height: 64px; display: flex; align-items: center; justify-content: space-between; }
.logo { display: flex; align-items: baseline; gap: 10px; color: #fff; }
.logo strong { font-size: 22px; letter-spacing: 2px; font-weight: 700; }
.logo span { font-size: 12px; letter-spacing: 4px; color: #94A3B8; }
.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a { color: #CBD5E1; font-size: 15px; transition: color .2s; cursor: pointer; }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: #fff; }
.btn-nav { background: var(--c-cta); color: #fff !important; padding: 9px 20px; border-radius: 8px; font-weight: 600; transition: background .2s; }
.btn-nav:hover { background: var(--c-cta-hover); }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle svg { display: block; }

/* ---------- Hero ---------- */
.hero { position: relative; min-height: 640px; display: flex; align-items: center; color: #fff;
  background: linear-gradient(rgba(15,23,42,.78), rgba(15,23,42,.55) 55%, rgba(15,23,42,.85)), url("../img/hero-car.jpg") center/cover no-repeat, var(--c-primary); }
.hero-inner { max-width: 1160px; margin: 0 auto; padding: 140px 24px 80px; width: 100%; }
.hero .kicker { display: inline-block; font-size: 13px; letter-spacing: 3px; color: #FDBA74; border: 1px solid rgba(253,186,116,.4); padding: 6px 14px; border-radius: 999px; margin-bottom: 24px; }
.hero h1 { font-size: clamp(32px, 5vw, 54px); font-weight: 700; line-height: 1.25; letter-spacing: 1px; }
.hero h1 em { font-style: normal; color: #F97316; }
.hero p.lead { margin-top: 20px; font-size: 18px; color: #CBD5E1; max-width: 640px; }
.hero-cta { margin-top: 36px; display: flex; gap: 16px; flex-wrap: wrap; }
.btn { display: inline-block; padding: 14px 30px; border-radius: 10px; font-weight: 600; font-size: 16px; transition: background .2s, border-color .2s; cursor: pointer; }
.btn-primary { background: var(--c-cta); color: #fff; }
.btn-primary:hover { background: var(--c-cta-hover); }
.btn-ghost { border: 1px solid rgba(255,255,255,.4); color: #fff; }
.btn-ghost:hover { border-color: #fff; background: rgba(255,255,255,.08); }
.hero-stats { margin-top: 56px; display: flex; gap: 48px; flex-wrap: wrap; }
.hero-stats .stat b { display: block; font-size: 30px; color: #F97316; }
.hero-stats .stat span { font-size: 14px; color: #94A3B8; }

/* ---------- 通用 Section ---------- */
.section { padding: 88px 0; }
.section.tint { background: #fff; }
.section-head { max-width: 720px; margin-bottom: 52px; }
.kicker-sm { font-size: 13px; letter-spacing: 3px; color: var(--c-accent); font-weight: 600; margin-bottom: 12px; display: block; }
.section-head h2 { font-size: clamp(26px, 3.4vw, 36px); font-weight: 700; line-height: 1.3; }
.section-head p { margin-top: 14px; color: var(--c-muted); font-size: 17px; }

/* ---------- 卡片 ---------- */
.grid { display: grid; gap: 24px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.card { background: var(--c-card); border: 1px solid var(--c-line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); transition: box-shadow .2s, border-color .2s; cursor: pointer; }
.card:hover { box-shadow: var(--shadow-md); border-color: #CBD5E1; }
.card img { width: 100%; aspect-ratio: 1 / 1; object-fit: cover; }
.card-body { padding: 22px; }
.card-body h3 { font-size: 18px; font-weight: 700; }
.card-body p { margin-top: 8px; font-size: 14.5px; color: var(--c-muted); }
.card-tag { display: inline-block; margin-top: 14px; font-size: 13px; font-weight: 600; color: var(--c-accent); }

/* ---------- 特性行 ---------- */
.feature-row { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; margin-bottom: 72px; }
.feature-row:last-child { margin-bottom: 0; }
.feature-row.reverse > .feature-media { order: 2; }
.feature-media img { border-radius: var(--radius); box-shadow: var(--shadow-md); }
.feature-text h3 { font-size: 24px; font-weight: 700; margin-bottom: 14px; }
.feature-text p { color: var(--c-muted); margin-bottom: 14px; }
.check-list li { position: relative; padding-left: 30px; margin-bottom: 10px; color: var(--c-text); }
.check-list li::before { content: ""; position: absolute; left: 0; top: 7px; width: 18px; height: 18px; border-radius: 50%;
  background: var(--c-accent) url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="3"><path d="M5 13l4 4L19 7"/></svg>') center/12px no-repeat; }

/* ---------- 事实块（GEO 摘录单元） ---------- */
.fact-block { background: #fff; border: 1px solid var(--c-line); border-left: 4px solid var(--c-accent); border-radius: var(--radius); padding: 28px 32px; margin: 40px 0; }
.fact-block h2, .fact-block h3 { font-size: 18px; margin-bottom: 16px; }
.fact-block dl { display: grid; grid-template-columns: 160px 1fr; row-gap: 10px; font-size: 15px; }
.fact-block dt { color: var(--c-muted); font-weight: 600; }
.fact-block dd { color: var(--c-text); }

/* ---------- 步骤 ---------- */
.steps { counter-reset: step; display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 24px; }
.step { background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius); padding: 26px; box-shadow: var(--shadow-sm); }
.step::before { counter-increment: step; content: "0" counter(step); display: inline-block; font-size: 14px; font-weight: 700; color: var(--c-accent); letter-spacing: 1px; margin-bottom: 12px; }
.step h3 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 14px; color: var(--c-muted); }

/* ---------- 表格 ---------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--c-line); border-radius: var(--radius); background: #fff; box-shadow: var(--shadow-sm); }
table { width: 100%; border-collapse: collapse; font-size: 15px; min-width: 560px; }
th, td { padding: 14px 20px; text-align: left; border-bottom: 1px solid var(--c-line); }
th { background: var(--c-primary); color: #fff; font-weight: 600; white-space: nowrap; }
td { color: var(--c-text); }
tr:last-child td { border-bottom: none; }
td.num { font-weight: 700; color: var(--c-accent); }

/* ---------- FAQ ---------- */
.faq details { background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius); margin-bottom: 14px; overflow: hidden; }
.faq summary { cursor: pointer; padding: 20px 24px; font-weight: 600; font-size: 16px; list-style: none; position: relative; padding-right: 48px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 22px; top: 50%; transform: translateY(-50%); font-size: 22px; color: var(--c-accent); transition: transform .2s; }
.faq details[open] summary::after { transform: translateY(-50%) rotate(45deg); }
.faq .faq-a { padding: 0 24px 22px; color: var(--c-muted); font-size: 15px; }

/* ---------- 装车实拍横排 ---------- */
.gallery-strip { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.gallery-strip figure { margin: 0; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); }
.gallery-strip img { width: 100%; height: 260px; object-fit: cover; }
.gallery-strip figcaption { font-size: 13px; color: var(--c-muted); padding: 10px 14px; background: #fff; }

/* ---------- CTA 带 ---------- */
.cta-band { background: linear-gradient(135deg, #B91C1C, #DC2626); color: #fff; padding: 72px 0; text-align: center; }
.cta-band h2 { font-size: clamp(24px, 3vw, 34px); font-weight: 700; }
.cta-band p { margin: 14px auto 30px; color: #FECACA; max-width: 560px; }
.cta-band .btn { background: #fff; color: var(--c-cta); }
.cta-band .btn:hover { background: #FEF2F2; }

/* ---------- 页脚 ---------- */
.footer { background: #0F172A; color: #94A3B8; padding: 64px 0 32px; font-size: 14px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 44px; }
.footer h4 { color: #fff; font-size: 15px; margin-bottom: 16px; }
.footer li { margin-bottom: 10px; }
.footer a:hover { color: #fff; }
.footer-brand strong { color: #fff; font-size: 20px; letter-spacing: 2px; display: block; margin-bottom: 10px; }
.footer-brand p { max-width: 300px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.08); padding-top: 24px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; }

/* ---------- 面包屑 / 页头 ---------- */
.breadcrumb { font-size: 13px; color: #94A3B8; margin-bottom: 20px; }
.breadcrumb a:hover { color: var(--c-accent); }
.page-hero { background: var(--c-primary); color: #fff; padding: 140px 0 64px; }
.page-hero h1 { font-size: clamp(28px, 4vw, 40px); }
.page-hero p { margin-top: 12px; color: #CBD5E1; max-width: 680px; }
.page-hero .breadcrumb a { color: #94A3B8; }

/* ---------- 车型库 ---------- */
.fitment-img { position: relative; }
.fitment-img .badge { position: absolute; top: 12px; left: 12px; background: rgba(15,23,42,.85); color: #fff; font-size: 12px; padding: 4px 10px; border-radius: 6px; }
.brand-group { margin-bottom: 56px; }
.brand-group h2 { font-size: 24px; margin-bottom: 20px; display: flex; align-items: center; gap: 12px; }
.brand-group h2::after { content: ""; flex: 1; height: 1px; background: var(--c-line); }
.model-thumbs { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 20px; }
.model-thumbs figure { margin: 0; }
.model-thumbs img { border-radius: var(--radius); border: 1px solid var(--c-line); }
.model-thumbs figcaption { font-size: 13px; color: var(--c-muted); margin-top: 8px; text-align: center; }

/* ---------- 表单 ---------- */
.form-card { background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius); padding: 36px; box-shadow: var(--shadow-sm); max-width: 640px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field { margin-bottom: 18px; }
.field label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 8px; }
.field input, .field select, .field textarea { width: 100%; padding: 12px 14px; border: 1px solid var(--c-line); border-radius: 8px; font-size: 15px; font-family: inherit; background: var(--c-bg); transition: border-color .2s; }
.field input:focus, .field select:focus, .field textarea:focus { outline: none; border-color: var(--c-accent); }
.form-note { font-size: 13px; color: #94A3B8; margin-top: 14px; }
.form-status { margin-top: 14px; font-size: 14px; font-weight: 600; }
.contact-cols { display: grid; grid-template-columns: 1.2fr .8fr; gap: 48px; align-items: start; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .gallery-strip { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav-links { position: fixed; inset: 64px 0 auto 0; background: #0F172A; flex-direction: column; align-items: stretch; padding: 20px 24px 28px; gap: 18px; display: none; border-bottom: 1px solid rgba(255,255,255,.1); }
  .nav-links.open { display: flex; }
  .nav-toggle { display: block; }
  .hero { min-height: 560px; }
  .hero-stats { gap: 28px; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .feature-row { grid-template-columns: 1fr; gap: 28px; margin-bottom: 48px; }
  .feature-row.reverse > .feature-media { order: 0; }
  .model-thumbs { grid-template-columns: 1fr 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .contact-cols { grid-template-columns: 1fr; }
  .section { padding: 60px 0; }
  .fact-block dl { grid-template-columns: 1fr; }
  .fact-block dd { margin-bottom: 6px; }
}