:root {
  --bg: #ffffff;
  --bg-alt: #f7f7f8;
  --ink: #111214;
  --ink-2: #4b4f57;
  --muted: #8a8f98;
  --line: #e8e9ec;
  --accent: #f26a1b;
  --radius: 16px;
  --max: 1120px;
  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: var(--font); font-size: 16px; line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 24px; }

/* ---------- 导航 ---------- */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px; height: 64px; padding: 0 max(24px, calc((100vw - var(--max)) / 2));
  background: rgba(255,255,255,.86); backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s;
}
.nav.scrolled { border-bottom-color: var(--line); }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: -.01em; }
.brand-mark {
  display: inline-grid; place-items: center; width: 30px; height: 30px;
  border-radius: 9px; background: var(--ink); color: #fff; font-size: 12px; font-weight: 800; letter-spacing: .04em;
}
.nav-links { display: flex; gap: 22px; margin-left: auto; }
.nav-links a {
  color: var(--ink-2); font-size: 14.5px; padding: 4px 0;
  border-bottom: 2px solid transparent; transition: color .2s, border-color .2s;
}
.nav-links a:hover, .nav-links a.active { color: var(--ink); border-bottom-color: var(--ink); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  height: 46px; padding: 0 22px; border-radius: 999px;
  font-size: 15px; font-weight: 600; border: 1px solid transparent;
  font-family: inherit; cursor: pointer;
  transition: transform .12s, background .15s, border-color .15s;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--ink); color: #fff; }
.btn-primary:hover { background: #000; }
.btn-ghost { border-color: var(--line); background: #fff; color: var(--ink); }
.btn-ghost:hover { border-color: #d4d6db; }
.btn-sm { height: 36px; padding: 0 16px; font-size: 13.5px; }

/* ---------- 入场动画（参考站点交互） ---------- */
.anim {
  opacity: 0; transform: translateY(28px);
  transition: opacity .7s cubic-bezier(.16,1,.3,1), transform .7s cubic-bezier(.16,1,.3,1);
  will-change: opacity, transform;
}
.anim-d1 { transition-delay: .06s; }
.anim-d2 { transition-delay: .14s; }
.anim-d3 { transition-delay: .22s; }
.anim-d4 { transition-delay: .3s; }
@media (prefers-reduced-motion: reduce) {
  .anim { opacity: 1 !important; transform: none !important; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------- hero ---------- */
.hero { padding: 132px 0 72px; }
.eyebrow {
  margin: 0 0 14px; font-size: 11.5px; font-weight: 700;
  letter-spacing: .16em; text-transform: uppercase; color: var(--accent);
}
h1 { font-size: clamp(40px, 6vw, 68px); line-height: 1.04; letter-spacing: -.035em; font-weight: 750; margin: 0 0 22px; }
h2 { font-size: clamp(28px, 3.6vw, 40px); line-height: 1.12; letter-spacing: -.025em; font-weight: 720; margin: 0 0 14px; }
h3 { font-size: 18px; letter-spacing: -.01em; margin: 0 0 10px; }
.lede { max-width: 640px; margin: 0 0 32px; font-size: 19px; color: var(--ink-2); }
.cta-row { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 60px; }

/* 数字条 */
.stats {
  display: grid; grid-template-columns: repeat(4, minmax(0,1fr));
  gap: 1px; margin: 0; background: var(--line);
  border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden;
}
.stats > div { background: #fff; padding: 22px 20px; }
.stats dt { font-size: 30px; font-weight: 750; letter-spacing: -.02em; line-height: 1.15; }
.stats dt .unit { font-size: 15px; font-weight: 600; color: var(--muted); margin-left: 3px; }
.stats dd { margin: 3px 0 0; font-size: 13.5px; color: var(--muted); }
.stat:hover .stat-val { transform: scale(1.08); }

/* ---------- 区块 ---------- */
.section { padding: 88px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { max-width: 720px; margin-bottom: 40px; }
.section-head .lede { font-size: 17px; margin-bottom: 0; }

/* ---------- 卡片（带光标跟随光晕） ---------- */
.grid { display: grid; gap: 16px; margin-top: 36px; }
.grid-3 { grid-template-columns: repeat(3, minmax(0,1fr)); }
.grid-2 { grid-template-columns: repeat(2, minmax(0,1fr)); }
.card {
  position: relative; overflow: hidden;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px;
  transition: border-color .2s, box-shadow .2s, transform .2s, background .2s;
}
.card:hover {
  border-color: #d8dae0; transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(17,18,20,.07);
}
.card::after {
  content: ""; position: absolute; inset: 0; pointer-events: none; z-index: 1; opacity: 0;
  transition: opacity .3s;
  background: radial-gradient(circle 140px at var(--mx,50%) var(--my,50%), rgba(17,18,20,.055), transparent 70%);
}
.card:hover::after { opacity: 1; }
.card p { margin: 0; color: var(--ink-2); font-size: 15px; }
.card-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 10px; }
.card-head h3 { margin: 0; }
.pill {
  font-size: 12.5px; font-weight: 600; color: var(--ink-2);
  background: var(--bg-alt); border: 1px solid var(--line);
  padding: 4px 10px; border-radius: 999px; white-space: nowrap;
}

/* ---------- 载具预览（lightbox） ---------- */
.shots { display: grid; grid-template-columns: repeat(4, minmax(0,1fr)); gap: 12px; margin-top: 32px; }
.shot {
  position: relative; overflow: hidden; cursor: zoom-in;
  border: 1px solid var(--line); border-radius: var(--radius); background: #f4f4f5;
  aspect-ratio: 1/1; transition: transform .2s, border-color .2s, box-shadow .2s;
}
.shot img { width: 100%; height: 100%; object-fit: contain; display: block; }
.shot:hover { transform: translateY(-3px); border-color: #cfd1d7; box-shadow: 0 8px 22px rgba(17,18,20,.08); }
.shot span {
  position: absolute; left: 10px; bottom: 8px; z-index: 2;
  font-size: 11.5px; font-weight: 600; color: var(--ink);
  background: rgba(255,255,255,.9); border: 1px solid var(--line);
  border-radius: 999px; padding: 2px 9px;
}

/* ---------- 列表 / 表格 ---------- */
.checklist { list-style: none; margin: 24px 0 0; padding: 0; max-width: 720px; }
.checklist li {
  position: relative; padding: 11px 0 11px 30px; color: var(--ink-2); font-size: 15.5px;
  border-top: 1px solid var(--line);
}
.checklist li::before {
  content: ""; position: absolute; left: 3px; top: 19px; width: 12px; height: 7px;
  border-left: 2px solid var(--accent); border-bottom: 2px solid var(--accent); transform: rotate(-45deg);
}
.table { width: 100%; border-collapse: collapse; margin-top: 24px; font-size: 14.5px; }
.table th, .table td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--line); }
.table th { font-size: 12.5px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.table td { color: var(--ink-2); }
.table tbody tr:hover td { background: var(--bg-alt); }
.muted { color: var(--muted); }

/* ---------- CTA ---------- */
.cta-card {
  position: relative; overflow: hidden;
  display: flex; align-items: center; justify-content: space-between; gap: 24px;
  background: var(--ink); color: #fff; border-radius: 24px; padding: 48px 44px;
}
.cta-card h2 { margin: 0 0 8px; font-size: 30px; color: #fff; }
.cta-card p { margin: 0; color: rgba(255,255,255,.72); max-width: 520px; }
.cta-card .btn-primary { background: #fff; color: var(--ink); }
.cta-card::after {
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: 0; transition: opacity .3s;
  background: radial-gradient(circle 180px at var(--mx,50%) var(--my,50%), rgba(255,255,255,.12), transparent 70%);
}
.cta-card:hover::after { opacity: 1; }

/* ---------- footer ---------- */
.footer { border-top: 1px solid var(--line); padding: 44px 0 64px; background: #fff; }
.footer-inner { display: grid; gap: 10px; }
.footer p { margin: 0; color: var(--ink-2); font-size: 14px; }
.footer .muted { font-size: 13px; }
.footer-links { display: flex; gap: 18px; font-size: 13.5px; margin: 2px 0 6px; }
.footer-links a { color: var(--ink-2); }
.footer-links a:hover { color: var(--ink); }

/* ---------- 子页 ---------- */
.page-head { padding: 132px 0 8px; }
.page-head h1 { font-size: clamp(32px, 4.6vw, 48px); }
.page-body { padding: 24px 0 96px; }
.prose { max-width: 760px; }
.prose h2 { margin: 36px 0 10px; font-size: 24px; }
.prose p, .prose li { color: var(--ink-2); }
.prose li { margin: 6px 0 6px 20px; }
.dl-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 16px; margin-top: 32px; }
.note {
  margin-top: 28px; padding: 16px 18px; border: 1px solid var(--line); border-radius: 12px;
  background: var(--bg-alt); color: var(--ink-2); font-size: 14px;
}
.filter-btn.is-on { background: var(--ink); color: #fff; border-color: var(--ink); }

/* ---------- lightbox / modal ---------- */
.lightbox, .modal {
  display: none; position: fixed; z-index: 200; inset: 0;
  justify-content: center; align-items: center; padding: 24px;
}
.lightbox { background: rgba(10,10,12,.9); cursor: zoom-out; }
.lightbox.active, .modal.active { display: flex; }
.lightbox img { max-width: 92vw; max-height: 86vh; object-fit: contain; border-radius: 8px; background: #fff; }
.lightbox .hint { position: absolute; bottom: 16px; font-size: 12.5px; color: rgba(255,255,255,.55); }
.modal { background: rgba(17,18,20,.42); backdrop-filter: blur(6px); }
.modal-card {
  position: relative; background: #fff; border-radius: 18px;
  width: min(680px, 92vw); max-height: 82vh; overflow-y: auto; padding: 28px 26px;
  box-shadow: 0 24px 70px rgba(17,18,20,.22);
}
.modal-card h3 { font-size: 20px; margin-bottom: 12px; }
.modal-card p { font-size: 14.5px; line-height: 1.75; margin-bottom: 10px; color: var(--ink-2); }
.modal-card .close-btn {
  position: absolute; top: 14px; right: 14px;
  background: none; border: 0; color: var(--muted); font-size: 20px; cursor: pointer; padding: 4px 8px;
}
.modal-card .close-btn:hover { color: var(--ink); }
.modal-card .src { font-size: 12.5px; color: var(--muted); margin-top: 14px; border-top: 1px solid var(--line); padding-top: 12px; }
body.modal-open { overflow: hidden; }

@media (max-width: 960px) {
  .grid-3 { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .shots { grid-template-columns: repeat(2, minmax(0,1fr)); }
}
@media (max-width: 720px) {
  .nav { gap: 12px; }
  .nav-links { display: none; }
  .hero { padding: 108px 0 56px; }
  .stats { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .grid-3, .grid-2, .dl-grid { grid-template-columns: 1fr; }
  .cta-card { flex-direction: column; align-items: flex-start; padding: 32px 26px; }
}