/* ============================================================
   诸暨市大唐启东弹簧厂 · 官网样式
   Zhuji Datang Qidong Spring Factory
   ============================================================ */
:root {
  --blue: #0a4d8c;
  --blue-dark: #082e52;
  --blue-deep: #061f38;
  --blue-soft: #e8f1fa;
  --amber: #e8a33d;
  --amber-dark: #c9861f;
  --ink: #1c2733;
  --ink-2: #45566a;
  --ink-3: #7a8a9c;
  --line: #dfe6ee;
  --bg: #f5f7fa;
  --card: #ffffff;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(8, 46, 82, .08);
  --shadow-lg: 0 18px 50px rgba(8, 46, 82, .16);
  --maxw: 1180px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}
img { max-width: 100%; display: block; }
a { color: var(--blue); text-decoration: none; }
ul { list-style: none; }

.wrap { 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(10px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between;
  height: 68px;
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark { width: 42px; height: 42px; flex: none; }
.brand-text .cn { font-size: 19px; font-weight: 700; color: var(--blue-dark); letter-spacing: 1px; line-height: 1.2; }
.brand-text .en { font-size: 10.5px; color: var(--ink-3); letter-spacing: 2.5px; text-transform: uppercase; }

.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
  display: block; padding: 8px 16px; border-radius: 8px;
  color: var(--ink-2); font-size: 15px; font-weight: 500;
  transition: all .2s;
}
.main-nav a:hover { color: var(--blue); background: var(--blue-soft); }
.main-nav a.active { color: var(--blue); background: var(--blue-soft); font-weight: 600; }

.lang-switch {
  margin-left: 14px; display: flex; border: 1.5px solid var(--blue);
  border-radius: 999px; overflow: hidden; font-size: 12.5px; font-weight: 700;
}
.lang-switch button {
  border: 0; background: transparent; color: var(--blue);
  padding: 5px 13px; cursor: pointer; font: inherit; letter-spacing: .5px;
}
.lang-switch button.on { background: var(--blue); color: #fff; }

.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2.5px; background: var(--blue-dark); margin: 5px 0; border-radius: 2px; }

/* ---------- Hero ---------- */
.hero {
  position: relative; color: #fff; overflow: hidden;
  background: var(--blue-deep);
}
.hero-media {
  position: absolute; inset: 0;
  background-size: cover; background-position: center;
  opacity: .38;
}
.hero-media::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(100deg, rgba(6, 31, 56, .92) 22%, rgba(6, 31, 56, .35) 70%, rgba(6, 31, 56, .55));
}
.hero-inner {
  position: relative; max-width: var(--maxw); margin: 0 auto; padding: 110px 24px 130px;
}
.hero-kicker {
  display: inline-flex; align-items: center; gap: 8px;
  background: rgba(232, 163, 61, .16); border: 1px solid rgba(232, 163, 61, .55);
  color: #f4c67c; font-size: 13px; letter-spacing: 2px;
  padding: 6px 16px; border-radius: 999px; margin-bottom: 26px;
}
.hero h1 {
  font-size: clamp(30px, 4.6vw, 52px); line-height: 1.25; font-weight: 800;
  max-width: 760px; letter-spacing: 1px;
}
.hero h1 em { font-style: normal; color: var(--amber); }
.hero .sub {
  margin-top: 22px; font-size: clamp(15px, 1.6vw, 18px);
  color: #c9d8e8; max-width: 640px;
}
.hero-actions { margin-top: 38px; display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
  display: inline-block; padding: 13px 32px; border-radius: 10px;
  font-size: 15.5px; font-weight: 600; letter-spacing: 1px;
  transition: all .2s; border: 1.5px solid transparent;
}
.btn-primary { background: var(--amber); color: #2b1a02; }
.btn-primary:hover { background: #f0b155; transform: translateY(-2px); box-shadow: 0 10px 24px rgba(232, 163, 61, .35); }
.btn-ghost { border-color: rgba(255, 255, 255, .55); color: #fff; }
.btn-ghost:hover { background: rgba(255, 255, 255, .12); }
.btn-blue { background: var(--blue); color: #fff; }
.btn-blue:hover { background: var(--blue-dark); transform: translateY(-2px); }

/* ---------- Stats bar ---------- */
.stats-band { background: var(--blue-dark); color: #fff; }
.stats-grid {
  max-width: var(--maxw); margin: 0 auto; padding: 34px 24px;
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px;
}
.stat { text-align: center; padding: 8px 6px; }
.stat b { display: block; font-size: clamp(26px, 3vw, 38px); font-weight: 800; color: #fff; line-height: 1.2; }
.stat b i { font-style: normal; font-size: .55em; color: var(--amber); margin-left: 2px; }
.stat span { display: block; margin-top: 6px; font-size: 13.5px; color: #a9bfd4; letter-spacing: 1px; }

/* ---------- Sections ---------- */
.section { padding: 84px 0; }
.section.alt { background: #fff; }
.sec-head { text-align: center; max-width: 720px; margin: 0 auto 52px; }
.sec-head .eyebrow {
  color: var(--amber-dark); font-size: 13px; font-weight: 700;
  letter-spacing: 3px; text-transform: uppercase;
}
.sec-head h2 {
  margin-top: 10px; font-size: clamp(24px, 3vw, 34px);
  color: var(--blue-dark); font-weight: 800; letter-spacing: 1px;
}
.sec-head p { margin-top: 14px; color: var(--ink-2); font-size: 15.5px; }

/* ---------- Cards ---------- */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }

.icon-card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 26px; transition: all .25s;
}
.icon-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg); border-color: transparent; }
.icon-card .num {
  width: 46px; height: 46px; border-radius: 12px; background: var(--blue-soft);
  color: var(--blue); font-weight: 800; font-size: 19px;
  display: flex; align-items: center; justify-content: center; margin-bottom: 18px;
}
.icon-card h3 { font-size: 18px; color: var(--blue-dark); margin-bottom: 10px; }
.icon-card p { font-size: 14.5px; color: var(--ink-2); }

/* ---------- Product / app cards ---------- */
.photo-card {
  background: var(--card); border-radius: var(--radius); overflow: hidden;
  border: 1px solid var(--line); transition: all .25s; display: flex; flex-direction: column;
}
.photo-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg); }
.photo-card .ph { aspect-ratio: 4 / 3; overflow: hidden; background: #eef2f6; }
.photo-card .ph img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s; }
.photo-card:hover .ph img { transform: scale(1.06); }
.photo-card .body { padding: 20px 22px 24px; }
.photo-card h3 { font-size: 17px; color: var(--blue-dark); }
.photo-card .en-sub { font-size: 12px; color: var(--ink-3); letter-spacing: 1px; margin-top: 2px; text-transform: uppercase; }
.photo-card p { margin-top: 10px; font-size: 14px; color: var(--ink-2); }

/* ---------- Split (image + text) ---------- */
.split { display: grid; grid-template-columns: 1.05fr 1fr; gap: 54px; align-items: center; }
.split .img-side { border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-lg); }
.split h2 { font-size: clamp(23px, 2.6vw, 32px); color: var(--blue-dark); font-weight: 800; }
.split .lead { margin: 18px 0 8px; color: var(--ink-2); }
.check-list { margin-top: 18px; }
.check-list li {
  position: relative; padding: 9px 0 9px 30px; color: var(--ink);
  font-size: 15px; border-bottom: 1px dashed var(--line);
}
.check-list li::before {
  content: "✓"; position: absolute; left: 2px; top: 9px;
  color: var(--amber-dark); font-weight: 800;
}

/* ---------- Sales bars ---------- */
.bar-row { margin-bottom: 18px; }
.bar-row .bar-label { display: flex; justify-content: space-between; font-size: 14.5px; color: var(--ink-2); margin-bottom: 7px; }
.bar-row .bar-label b { color: var(--blue-dark); }
.bar-track { height: 12px; background: #e6ecf3; border-radius: 999px; overflow: hidden; }
.bar-fill { height: 100%; border-radius: 999px; background: linear-gradient(90deg, var(--blue), #2f7fc2); }
.bar-fill.amber { background: linear-gradient(90deg, var(--amber-dark), var(--amber)); }

/* ---------- Timeline ---------- */
.timeline { position: relative; max-width: 860px; margin: 0 auto; padding-left: 30px; }
.timeline::before {
  content: ""; position: absolute; left: 8px; top: 6px; bottom: 6px;
  width: 3px; background: linear-gradient(var(--blue), var(--amber)); border-radius: 3px;
}
.tl-item { position: relative; padding: 0 0 34px 26px; }
.tl-item::before {
  content: ""; position: absolute; left: -30px; top: 7px;
  width: 17px; height: 17px; border-radius: 50%;
  background: #fff; border: 4px solid var(--blue);
}
.tl-item:last-child { padding-bottom: 0; }
.tl-item .year { font-size: 21px; font-weight: 800; color: var(--blue); }
.tl-item h4 { font-size: 16.5px; margin: 4px 0 4px; color: var(--ink); }
.tl-item p { font-size: 14.5px; color: var(--ink-2); }

/* ---------- Process steps ---------- */
.steps { counter-reset: step; display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; }
.step {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 18px; text-align: center; position: relative; transition: all .25s;
}
.step:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--blue); }
.step::before {
  counter-increment: step; content: counter(step);
  display: inline-flex; width: 38px; height: 38px; border-radius: 50%;
  background: var(--blue); color: #fff; font-weight: 800; font-size: 16px;
  align-items: center; justify-content: center; margin-bottom: 14px;
}
.step h4 { font-size: 15.5px; color: var(--blue-dark); margin-bottom: 6px; }
.step p { font-size: 13px; color: var(--ink-3); line-height: 1.6; }

/* ---------- Gallery ---------- */
.gallery { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.gallery figure { border-radius: var(--radius); overflow: hidden; position: relative; margin: 0; }
.gallery img { width: 100%; height: 240px; object-fit: cover; transition: transform .5s; }
.gallery figure:hover img { transform: scale(1.07); }
.gallery figcaption {
  position: absolute; left: 0; right: 0; bottom: 0;
  padding: 26px 16px 12px; color: #fff; font-size: 13.5px; letter-spacing: 1px;
  background: linear-gradient(transparent, rgba(6, 31, 56, .85));
}

/* ---------- Cert chips ---------- */
.chip-row { display: flex; flex-wrap: wrap; gap: 12px; }
.chip {
  background: var(--card); border: 1px solid var(--line); border-radius: 999px;
  padding: 9px 22px; font-size: 14px; color: var(--blue-dark); font-weight: 600;
  display: inline-flex; align-items: center; gap: 8px;
}
.chip::before { content: "◈"; color: var(--amber-dark); }

/* ---------- Client wall ---------- */
.client-wall { display: grid; grid-template-columns: repeat(6, 1fr); gap: 14px; }
.client-cell {
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  min-height: 86px; display: flex; flex-direction: column; gap: 2px;
  align-items: center; justify-content: center; text-align: center; padding: 12px 8px;
  transition: all .25s;
}
.client-cell:hover { border-color: var(--blue); box-shadow: var(--shadow); }
.client-cell b { font-size: 16px; color: var(--blue-dark); }
.client-cell span { font-size: 11px; color: var(--ink-3); letter-spacing: 1px; text-transform: uppercase; }

/* ---------- CTA ---------- */
.cta-band { background: linear-gradient(115deg, var(--blue-deep), var(--blue) 70%); color: #fff; }
.cta-inner { max-width: var(--maxw); margin: 0 auto; padding: 66px 24px; display: flex; align-items: center; justify-content: space-between; gap: 30px; flex-wrap: wrap; }
.cta-inner h2 { font-size: clamp(22px, 2.8vw, 30px); letter-spacing: 1px; }
.cta-inner p { color: #b9cfe3; margin-top: 8px; }

/* ---------- Contact page ---------- */
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.contact-card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 26px; text-align: center;
}
.contact-card .ic { font-size: 30px; margin-bottom: 12px; }
.contact-card h3 { color: var(--blue-dark); font-size: 17px; margin-bottom: 8px; }
.contact-card p { color: var(--ink-2); font-size: 15px; }
.contact-card a { font-weight: 700; font-size: 19px; letter-spacing: 1px; }

.form-note { background: #fff8ec; border: 1px solid #f2ddb4; border-radius: 12px; padding: 18px 22px; color: #7a5a1e; font-size: 14.5px; margin-top: 26px; }

/* ---------- Footer ---------- */
.site-footer { background: var(--blue-deep); color: #9fb4c8; margin-top: 0; }
.footer-grid {
  max-width: var(--maxw); margin: 0 auto; padding: 58px 24px 40px;
  display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 44px;
}
.site-footer h4 { color: #fff; font-size: 15.5px; margin-bottom: 16px; letter-spacing: 1px; }
.site-footer p, .site-footer li { font-size: 13.5px; line-height: 2; }
.site-footer a { color: #9fb4c8; }
.site-footer a:hover { color: #fff; }
.footer-brand .cn { color: #fff; font-size: 20px; font-weight: 700; letter-spacing: 1px; }
.footer-brand .en { font-size: 11px; letter-spacing: 2.5px; color: #6f89a3; text-transform: uppercase; margin-top: 2px; }
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, .1);
  padding: 18px 24px; text-align: center; font-size: 12.5px; color: #6f89a3;
}

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .grid-3, .grid-4, .steps { grid-template-columns: repeat(2, 1fr); }
  .split { grid-template-columns: 1fr; gap: 30px; }
  .client-wall { grid-template-columns: repeat(3, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .gallery { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
}
@media (max-width: 720px) {
  .main-nav {
    position: fixed; inset: 68px 0 auto 0; background: #fff;
    flex-direction: column; align-items: stretch; padding: 14px 20px 22px;
    border-bottom: 1px solid var(--line); box-shadow: var(--shadow-lg);
    display: none;
  }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 13px 10px; font-size: 16px; }
  .lang-switch { margin: 10px 0 0; align-self: flex-start; }
  .nav-toggle { display: block; }
  .grid-3, .grid-4, .steps, .grid-2 { grid-template-columns: 1fr; }
  .hero-inner { padding: 80px 24px 90px; }
  .section { padding: 60px 0; }
  .client-wall { grid-template-columns: repeat(2, 1fr); }
}