/* ============================================================
   BRABUS Lubricants — light professional theme (Western B2B)
   ============================================================ */
:root {
  --bg: #ffffff;
  --bg2: #f6f8fb;
  --panel: #ffffff;
  --panel2: #f1f5f9;
  --line: #e2e8f0;
  --text: #0f172a;
  --muted: #5b6b7f;
  --blue: #e5c82e;
  --blue2: #f0d94a;
  --blue-deep: #8f7509;   /* 文字专用深金：浅底可读 */
  --red: #e04545;
  --shadow: 0 4px 18px rgba(15, 23, 42, .06);
  --shadow-lg: 0 16px 40px rgba(15, 23, 42, .10);
  --radius: 14px;
  --maxw: 1200px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body { overflow-x: hidden; -webkit-tap-highlight-color: transparent; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px; line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}.header-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand img { height: 34px; width: auto; }
.nav { display: flex; align-items: center; gap: 28px; }
.nav > a {
  font-size: 13px; font-weight: 600; letter-spacing: .14em;
  color: var(--muted); padding: 6px 0; border-bottom: 2px solid transparent;
  transition: color .2s;
}
.nav > a:hover { color: var(--text); }
.nav > a.active { color: var(--text); border-bottom-color: var(--blue-deep); }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 9px 8px; margin-right: -8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text); margin: 5px 0; transition: .25s; }

/* ---------- buttons / chips / badges ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 26px; border-radius: 8px;
  font-size: 14px; font-weight: 700; letter-spacing: .04em;
  cursor: pointer; border: 1px solid transparent; transition: .2s;
}
.btn-primary { background: var(--blue); color: #14160f; }
.btn-primary:hover { background: var(--blue2); transform: translateY(-1px); box-shadow: 0 8px 20px rgba(229,200,46,.32); }
.btn-ghost { border-color: var(--line); color: var(--text); background: #fff; }
.btn-ghost:hover { border-color: var(--blue-deep); color: var(--blue-deep); }
.btn-wa { background: #eef9f0; border-color: #bfe6c8; color: #1a7f37; }
.btn-wa:hover { background: #e0f4e5; }
.btn-sm { padding: 8px 16px; font-size: 12px; }
.btn-lg { padding: 16px 36px; font-size: 15px; }

.chip {
  display: inline-block; padding: 7px 16px; border-radius: 999px;
  background: #fff; border: 1px solid var(--line);
  color: var(--muted); font-size: 13px; font-weight: 600;
  cursor: pointer; transition: .18s;
}
.chip:hover { color: var(--text); border-color: #d8cf9e; }
.chip-on { background: var(--blue); border-color: var(--blue-deep); color: #14160f; }
.chip-mini { padding: 3px 10px; font-size: 11px; font-weight: 600; cursor: default; }
.chip-vis { color: var(--blue-deep); border-color: #e8dfa8; background: #fdfaec; }
.badge {
  display: inline-block; padding: 5px 14px; border-radius: 6px;
  background: var(--panel2); border: 1px solid var(--line);
  font-size: 12px; font-weight: 700; letter-spacing: .08em; color: var(--muted);
}
.badge-api { border-color: #ded29a; color: var(--blue-deep); background: #fdf8e3; }
.cert-chip {
  padding: 5px 14px; border: 1px solid var(--line); border-radius: 6px;
  font-size: 12px; font-weight: 700; color: var(--muted); letter-spacing: .1em; background: #fff;
}

/* ---------- hero ---------- */
.hero {
  padding: 88px 0 72px;
  background:
    radial-gradient(900px 500px at 85% 0%, rgba(37,99,235,.07), transparent 60%),
    radial-gradient(600px 400px at 5% 95%, rgba(37,99,235,.04), transparent 60%),
    linear-gradient(180deg, #fbfcfe 0%, #ffffff 100%);
  border-bottom: 1px solid var(--line);
}
.hero-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 56px; align-items: center; }
.hero-kicker { font-size: 12px; font-weight: 700; letter-spacing: .22em; color: var(--blue-deep); margin-bottom: 18px; }
.hero h1 { font-size: 56px; line-height: 1.08; font-weight: 800; letter-spacing: -.01em; color: #0b1526; }
.hero h1 .accent { color: var(--blue-deep); }
.hero-sub { color: var(--muted); font-size: 17px; margin: 22px 0 30px; max-width: 520px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-certs { display: flex; gap: 10px; margin-top: 34px; flex-wrap: wrap; }
.hero-card {
  background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 26px;
  box-shadow: var(--shadow-lg);
  transform: rotate(1.2deg);
  transition: transform .35s ease;
}
.hero-card:hover { transform: rotate(0deg) scale(1.02); }
.hero-card img { border-radius: 10px; }
.hero-card-tag {
  margin-top: 14px; text-align: center; font-size: 12px; font-weight: 700;
  letter-spacing: .1em; color: #33445c;
}

/* ---------- hero variant: full-bleed factory photo ---------- */
/* 备份见 _backup_hero_v1_* 目录，回滚只需把 index.html 的 hero 段落还原 */
/* 固定高度 + cover 裁剪：图片等比铺满、超出部分裁掉，储罐群居中偏下 */
.hero-photo {
  position: relative; overflow: hidden;
  height: 560px;
  background: #0a1226;
  border-bottom: 1px solid var(--line);
}
.hero-photo .hero-bg {
  position: absolute; inset: 0; width: 100%; height: 100%;
  object-fit: cover; object-position: center 68%;
}
.hero-photo .hero-shade {
  position: absolute; inset: 0; z-index: 1;
  background: rgba(4,9,20,.62);
}
.hero-photo .container {
  position: absolute; inset: 0; z-index: 2;
  display: flex; flex-direction: column; justify-content: center;
}
.hero-photo .hero-copy { max-width: 760px; }
.hero-photo .hero-kicker { color: #ffdc55; }
.hero-photo h1 { color: #ffffff; font-size: 48px; white-space: nowrap; }
.hero-photo h1 .accent { color: #ffdb4d; }
.hero-photo .hero-sub { color: rgba(255,255,255,.86); max-width: 560px; }
.hero-photo .cert-chip {
  background: rgba(255,255,255,.10); border-color: rgba(255,255,255,.28);
  color: rgba(255,255,255,.92);
}
.hero-photo .btn-wa { background: rgba(37,211,102,.16); border-color: rgba(37,211,102,.55); color: #7fe3a4; }
.hero-photo .btn-wa:hover { background: rgba(37,211,102,.28); }

@media (max-width: 1180px) {
  .hero-photo { height: 480px; }
  .hero-photo .hero-bg { object-position: center 62%; }
  .hero-photo h1 { font-size: 42px; white-space: normal; }
}
/* ≤980px：固定高度改弹性高度（min-height + 随内容增长），杜绝窄屏下文字/按钮溢出裁切 */
@media (max-width: 980px) {
  .hero-photo { height: auto; min-height: 430px; display: flex; padding: 0; }
  .hero-photo .hero-bg { object-position: center 58%; }
  .hero-photo .container { position: relative; inset: auto; padding-top: 52px; padding-bottom: 56px; }
  .hero-photo .hero-copy { max-width: 100%; }
  .hero-photo h1 { font-size: 34px; white-space: normal; }
  .hero-photo .hero-sub { max-width: 100%; }
}
@media (max-width: 640px) {
  .hero-photo { min-height: 380px; }
  .hero-photo .container { padding-top: 44px; padding-bottom: 48px; }
  .hero-photo h1 { font-size: 30px; }
  .hero-photo .hero-sub { font-size: 15px; }
}
@media (max-width: 420px) {
  .hero-photo h1 { font-size: 27px; }
}

/* ---------- stats band ---------- */
.stats { border-bottom: 1px solid var(--line); background: var(--bg2); }
.stats-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; padding: 36px 0; }
.stat { text-align: center; }
.stat-num { font-size: 34px; font-weight: 800; color: var(--blue-deep); font-variant-numeric: tabular-nums; }
.stat-unit { font-size: 12.5px; color: var(--muted); margin-top: 2px; }

/* ---------- sections ---------- */
.section { padding: 84px 0; }
.section-alt { background: var(--bg2); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { max-width: 640px; margin-bottom: 44px; }
.kicker { font-size: 12px; font-weight: 700; letter-spacing: .22em; color: var(--blue-deep); margin-bottom: 12px; }
.section-head h2, .group-title { font-size: 34px; font-weight: 800; letter-spacing: -.01em; color: #0b1526; }
.section-sub { color: var(--muted); margin-top: 14px; }

/* ---------- category cards ---------- */
.cat-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
.cat-card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; transition: .25s; box-shadow: var(--shadow);
}
.cat-card:hover { border-color: #d8cf9e; transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.cat-media { background: #fff; aspect-ratio: 4 / 3; display: flex; align-items: center; justify-content: center; padding: 12px; }
.cat-media img { width: 100%; height: 100%; object-fit: contain; }
.cat-body { padding: 26px 28px 30px; }
.cat-body h3 { font-size: 21px; margin-bottom: 10px; }
.cat-body p { color: var(--muted); font-size: 14.5px; }
.cat-desc-short { display: none; }   /* 默认（桌面）用长描述 */
.cat-link { display: inline-block; margin-top: 16px; color: var(--blue-deep); font-weight: 700; font-size: 14px; }

/* ---------- feature cards ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.feature-card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px 24px; box-shadow: var(--shadow); }
.feature-ico {
  width: 46px; height: 46px; border-radius: 10px; display: flex; align-items: center; justify-content: center;
  background: #fdf8e3; color: var(--blue-deep); font-weight: 800; font-size: 13px; letter-spacing: .05em;
  border: 1px solid #d4e2fa; margin-bottom: 18px;
}
.feature-card h3 { font-size: 17px; margin-bottom: 8px; }
.feature-card p { color: var(--muted); font-size: 14px; }

/* ---------- product listing ---------- */
.page-head { padding: 64px 0 40px; background: var(--bg2); border-bottom: 1px solid var(--line); }
.crumbs { font-size: 13px; color: var(--muted); margin-bottom: 16px; }
.crumbs a:hover { color: var(--blue-deep); }
.crumbs span { color: var(--text); }
.page-head h1 { font-size: 42px; font-weight: 800; color: #0b1526; }
.page-sub { color: var(--muted); margin-top: 10px; }
.filter-bar { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 40px; }
.prod-group { margin-bottom: 64px; }
.group-title { font-size: 26px; margin-bottom: 8px; }
.group-desc { color: var(--muted); font-size: 15px; max-width: 720px; margin-bottom: 26px; }
.prod-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 22px; }
.prod-card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; transition: .22s; display: flex; flex-direction: column; box-shadow: var(--shadow);
}
.prod-card:hover { border-color: #d8cf9e; transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.prod-media { position: relative; background: #fff; aspect-ratio: 4 / 3; display: flex; align-items: center; justify-content: center; padding: 10px; }
.prod-media img { width: 100%; height: 100%; object-fit: contain; }
.prod-badge {
  position: absolute; top: 10px; right: 10px;
  background: rgba(11,21,38,.82); color: #fff; font-size: 11px; font-weight: 700;
  padding: 4px 10px; border-radius: 6px; letter-spacing: .05em;
}
.prod-body { padding: 18px 18px 20px; flex: 1; }
.prod-name { font-weight: 800; font-size: 17px; }
.prod-full { color: var(--muted); font-size: 13px; margin: 3px 0 12px; min-height: 20px; }
.prod-chips { display: flex; flex-wrap: wrap; gap: 6px; }

/* ---------- product detail ---------- */
.detail-section { padding: 56px 0 72px; }
.detail-grid { display: grid; grid-template-columns: minmax(0,1fr) minmax(0,1fr); gap: 52px; align-items: start; }
.viewer {
  background: #fff; border-radius: 18px; padding: 18px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-lg);
  position: relative;
}
.viewer-stage {
  position: relative; aspect-ratio: 1 / 1; overflow: hidden;
  border-radius: 10px;
  background: #fff;
}
.v-img {
  position: absolute; inset: 0; width: 100%; height: 100%; object-fit: contain;
  opacity: 0; transition: opacity .18s ease, transform .18s ease;
  pointer-events: none; user-select: none;
}
.v-img.active { opacity: 1; pointer-events: auto; }
.viewer-single .v-img { position: static; width: 100%; }
.variant-bar { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-top: 22px; }
.variant-label { font-size: 13px; font-weight: 700; color: var(--muted); letter-spacing: .06em; }

.d-badges { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 18px; }
.d-title { font-size: 34px; font-weight: 800; line-height: 1.15; color: #0b1526; }
.d-grade { color: var(--muted); margin: 8px 0 26px; font-size: 15px; letter-spacing: .04em; }
.spec-table { width: 100%; border-collapse: collapse; margin-bottom: 30px; }
.spec-table th, .spec-table td {
  text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--line);
  font-size: 14.5px;
}
.spec-table th { color: var(--muted); font-weight: 600; width: 34%; white-space: nowrap; }
.spec-table td { font-weight: 600; }
/* Hidden applications row: delete this rule to show it on the page */
.hidden-app { display: none; }
.d-feats h3 { font-size: 13px; letter-spacing: .18em; color: var(--blue-deep); margin-bottom: 14px; }
.d-feats ul { list-style: none; }
.d-feats li {
  padding: 10px 0 10px 28px; border-bottom: 1px solid var(--line);
  color: #33445c; font-size: 14.5px; position: relative;
}
.d-feats li::before {
  content: "◆"; position: absolute; left: 2px; top: 10px;
  color: var(--blue-deep); font-size: 11px;
}
.d-actions { display: flex; gap: 14px; margin-top: 30px; flex-wrap: wrap; }
.rel-title { font-size: 24px; margin-bottom: 26px; color: #0b1526; }

/* ---------- about ---------- */
.about-grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: 56px; align-items: start; }
.about-copy h2 { font-size: 30px; margin-bottom: 22px; color: #0b1526; }
.about-copy p { color: #33445c; margin-bottom: 18px; }
.about-numbers {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 28px; display: grid; grid-template-columns: 1fr 1fr; gap: 20px 16px; margin-bottom: 26px;
  box-shadow: var(--shadow);
}
.about-numbers b { display: block; font-size: 24px; color: var(--blue-deep); font-weight: 800; }
.about-numbers span { font-size: 12.5px; color: var(--muted); }
.about-cert { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 28px; box-shadow: var(--shadow); }
.cert-list { list-style: none; }
.cert-list li { padding: 9px 0 9px 24px; font-size: 13.5px; color: #33445c; position: relative; border-bottom: 1px solid var(--line); }
.cert-list li::before { content: "✓"; position: absolute; left: 0; color: var(--blue-deep); font-weight: 800; }
.principle-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.principle { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 24px; box-shadow: var(--shadow); }
.principle h3 { font-size: 17px; margin-bottom: 8px; color: var(--blue-deep); }
.principle p { color: var(--muted); font-size: 14px; }

/* ---------- contact page ---------- */
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.contact-card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px 28px; text-align: center; transition: .22s; box-shadow: var(--shadow);
}
.contact-card:hover { border-color: #d8cf9e; transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.c-ico {
  width: 62px; height: 62px; margin: 0 auto 18px; border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  color: #fff; box-shadow: 0 6px 16px rgba(15,23,42,.16);
  transition: transform .2s ease;
}
.contact-card:hover .c-ico { transform: scale(1.06); }
.c-ico.wa { background: #25d366; }
.c-ico.mail { background: #e5c82e; color: #14160f; }
.c-ico.fb { background: #1877f2; }
.contact-card h3 { font-size: 17px; margin-bottom: 6px; }
.contact-card p { color: var(--muted); font-size: 14.5px; }
.c-cta { display: inline-block; margin-top: 16px; color: var(--blue-deep); font-weight: 700; font-size: 13.5px; }
.inquiry { text-align: center; }
.inquiry-note { color: var(--muted); font-size: 13.5px; margin-top: 16px; }

/* ---------- floating contact rail (right edge, all pages) ---------- */
.float-rail {
  position: fixed; right: 0; top: 50%; transform: translateY(-50%);
  z-index: 120; display: flex; flex-direction: column; gap: 10px;
  pointer-events: none;
}.rail-item {
  position: relative; display: flex; align-items: center; justify-content: center;
  width: 48px; height: 48px; border-radius: 10px 0 0 10px;
  color: #fff; box-shadow: 0 6px 18px rgba(15, 23, 42, .22);
  transition: transform .18s ease;
  pointer-events: auto;
}
.rail-item:hover { transform: translateX(-3px); }
.rail-wa { background: #25d366; }
.rail-mail { background: #e5c82e; color: #14160f !important; }
.rail-fb { background: #1877f2; }
.rail-tip {
  position: absolute; right: 56px; top: 50%;
  transform: translateY(-50%) translateX(8px);
  background: #0f172a; color: #fff; font-size: 12.5px; font-weight: 600;
  padding: 6px 12px; border-radius: 8px; white-space: nowrap;
  opacity: 0; pointer-events: none; transition: opacity .18s ease, transform .18s ease;
}
.rail-item:hover .rail-tip { opacity: 1; transform: translateY(-50%) translateX(0); }

/* ---------- cta band (dark industrial base with yellow accent) ---------- */
.cta-band { background: linear-gradient(120deg, #12151c, #1d2230 130%); border-top: 1px solid var(--line); }
.cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 30px; padding: 20px 0; flex-wrap: wrap; }
.cta-inner h2 { font-size: 28px; color: #fff; }
.cta-inner p { color: rgba(255,255,255,.68); margin-top: 6px; }
.cta-band .btn-primary { background: var(--blue); color: #14160f; }
.cta-band .btn-primary:hover { background: var(--blue2); box-shadow: none; }

/* ---------- footer (dark navy base — standard Western B2B) ---------- */
.site-footer { background: #0b1220; border-top: 1px solid #1a2740; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.4fr; gap: 40px; padding: 56px 24px 40px; }
.f-logo { margin-bottom: 16px; }
.f-desc { color: #8fa0b8; font-size: 13.5px; }
.f-col h4 { font-size: 12px; letter-spacing: .18em; color: #e9eef6; margin-bottom: 16px; }
.f-col a { display: block; color: #8fa0b8; font-size: 13.5px; padding: 5px 0; }
.f-col a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid #1a2740; padding: 20px 24px; font-size: 12.5px; color: #5d6a80; }

/* ---------- reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- responsive ---------- */
/* 触屏设备：取消位移型 hover，避免点按后卡片"粘住"悬浮态 */
@media (hover: none) {
  .cat-card:hover, .prod-card:hover, .contact-card:hover,
  .hero-card:hover, .btn-primary:hover, .contact-card:hover .c-ico, .rail-item:hover { transform: none; }
}
@media (max-width: 1180px) {
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(3, 1fr); gap: 20px 16px; }
  .principle-grid { grid-template-columns: 1fr 1fr; }
  .cta-inner { padding-right: 56px; }
}
@media (max-width: 980px) {
  .hero-grid, .detail-grid, .about-grid, .cat-grid { grid-template-columns: 1fr; }
  .feature-grid, .contact-grid { grid-template-columns: 1fr 1fr; }
  .principle-grid { grid-template-columns: 1fr 1fr; }
  .float-rail { gap: 8px; }
  .rail-item { width: 40px; height: 40px; border-radius: 8px 0 0 8px; }
  .rail-item svg { width: 18px; height: 18px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 860px) {
  .cta-inner { flex-direction: column; align-items: flex-start; gap: 20px; padding-right: 52px; }
  .cta-inner h2 { font-size: 24px; }
}

/* ---------- mobile（手机）---------- */
@media (max-width: 640px) {
  .container { padding: 0 20px; }

  /* 汉堡菜单：相对 header 定位（top:100%），不写死高度，杜绝缝隙 */
  .nav {
    position: absolute; top: 100%; left: 0; right: 0; z-index: 99;
    background: #fff; border-bottom: 1px solid var(--line);
    box-shadow: 0 16px 32px rgba(15, 23, 42, .10);
    flex-direction: column; align-items: flex-start; padding: 10px 24px 16px; gap: 2px;
    display: none;
  }
  .site-header { position: sticky; }
  .nav.open { display: flex; animation: navDrop .22s ease; }  .nav > a { width: 100%; padding: 13px 2px; border-bottom: none; font-size: 15px; }
  .nav > a.active { border-bottom-color: transparent; color: var(--blue-deep); }
  .nav-toggle { display: block; }
  .nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-toggle.open span:nth-child(2) { opacity: 0; }
  .nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  /* 筛选 chip 与详情页变体 chip：加高到触摸友好 */
  .chip { padding: 10px 18px; }
  .chip-mini { padding: 4px 11px; }
  .chip-vis { padding: 10px 18px; }
  .variant-bar .chip-vis { padding: 9px 16px; }
  /* 面包屑链接：扩大点按区 */
  .crumbs a { display: inline-block; padding: 4px 2px; }

  /* 首屏数据条：两列 + 缩小数字，"100,000 t" 不再撑破格子 */
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 22px 12px; padding: 28px 0; }
  .stat-num { font-size: 24px; }
  .stat-unit { font-size: 11.5px; }

  /* 区块节奏收紧 */
  .section { padding: 56px 0; }
  .section-head { margin-bottom: 30px; }
  .section-head h2 { font-size: 25px; }
  .section-sub { font-size: 14.5px; }

  /* 首页分类卡片：窄屏并排两列（改用短描述，保证两卡等高、句子完整） */
  .cat-grid { grid-template-columns: 1fr 1fr; gap: 14px; align-items: stretch; }
  .cat-card { display: flex; flex-direction: column; }
  .cat-media { padding: 8px; }
  .cat-body { padding: 14px 13px 16px; display: flex; flex-direction: column; flex: 1; }
  .cat-body h3 { font-size: 14.5px; line-height: 1.3; margin-bottom: 7px; min-height: 2.6em; }
  .cat-body p { font-size: 12px; line-height: 1.5; }
  .cat-desc-long { display: none; }
  .cat-desc-short { display: block; }
  .cat-link { font-size: 12px; margin-top: auto; padding-top: 10px; }

  /* 产品列表：单列大卡 */
  .page-head { padding: 44px 0 32px; }
  .page-head h1 { font-size: 30px; }
  .filter-bar { margin-bottom: 28px; }
  .prod-group { margin-bottom: 44px; }
  .group-title { font-size: 22px; }
  .prod-grid { grid-template-columns: 1fr; gap: 16px; }

  /* 产品详情 */
  .detail-section { padding: 36px 0 52px; }
  .detail-grid { gap: 28px; }
  .d-title { font-size: 25px; }
  .spec-table th, .spec-table td { font-size: 13.5px; padding: 10px 8px; }
  .d-actions .btn { flex: 1 1 100%; justify-content: center; }

  /* About */
  .about-copy h2 { font-size: 24px; }
  .about-numbers { gap: 18px 12px; padding: 22px; }

  /* 按钮通栏（Hero 双按钮、CTA 按钮） */
  .hero-actions .btn { flex: 1 1 100%; justify-content: center; }
  .cta-inner { padding-right: 0; }
  .cta-inner .btn { width: 100%; justify-content: center; }

  /* 右侧浮条：移动端改为底部横排固定条，彻底避开正文与按钮 */
  .float-rail {
    top: auto; bottom: 0; right: 0; left: 0;
    transform: none;
    flex-direction: row; justify-content: center; gap: 14px;
    padding: 9px 16px calc(9px + env(safe-area-inset-bottom, 0px));
    background: rgba(255, 255, 255, .94);
    backdrop-filter: blur(12px);
    border-top: 1px solid var(--line);
    box-shadow: 0 -6px 20px rgba(15, 23, 42, .08);
  }
  .rail-item {
    width: 42px; height: 42px;
    border-radius: 12px;              /* 底部横排：四角圆角，不再是左半圆 */
    box-shadow: 0 4px 12px rgba(15, 23, 42, .16);
  }
  .rail-item svg { width: 19px; height: 19px; }
  .rail-tip { display: none; }        /* 触屏无 hover，隐藏气泡提示 */
  .rail-item:hover { transform: none; }
  /* 底部固定条不遮挡页脚末尾内容 */
  .site-footer { padding-bottom: 76px; }
  .cta-band .cta-inner { padding-bottom: 22px; }

  /* 功能/理念/联系卡片单列 */
  .feature-grid, .principle-grid, .contact-grid { grid-template-columns: 1fr; }
  .contact-card { padding: 28px 22px; }
}
/* 小屏手机（iPhone SE / 320px 档）*/
@media (max-width: 420px) {
  .section-head h2 { font-size: 23px; }
  .stat-num { font-size: 22px; }
  .d-title { font-size: 23px; }
}
@keyframes navDrop {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}