:root {
  --primary: #0a2540;
  --primary-light: #113a5c;
  --accent: #00d4ff;
  --accent-soft: rgba(0, 212, 255, 0.12);
  --gold: #f6ad55;
  --gold-soft: rgba(246, 173, 85, 0.14);
  --ink: #1f2937;
  --ink-2: #4b5563;
  --muted: #9ca3af;
  --bg: #f8fafc;
  --bg-white: #ffffff;
  --bg-alt: #f1f5f9;
  --line: #e2e8f0;
  --radius: 16px;
  --radius-sm: 10px;
  --maxw: 1280px;
  --shadow: 0 10px 40px -10px rgba(10, 37, 64, 0.15);
  --shadow-lg: 0 25px 60px -15px rgba(10, 37, 64, 0.25);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
.container { width: min(var(--maxw), 92%); margin: 0 auto; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; flex-direction: column; line-height: 1.15; }
.brand-cn { font-size: 20px; font-weight: 800; letter-spacing: 1px; color: var(--primary); }
.brand-en { font-size: 10px; color: var(--muted); letter-spacing: 3px; }
.nav-links { display: flex; gap: 32px; }
.nav-links a { font-size: 15px; color: var(--ink-2); position: relative; padding: 4px 0; transition: color .2s; }
.nav-links a:hover { color: var(--primary); }
.nav-links a::after {
  content: ""; position: absolute; left: 0; bottom: -2px; width: 0; height: 2px;
  background: var(--accent); transition: width .25s;
}
.nav-links a:hover::after { width: 100%; }
.nav-phone { font-weight: 700; color: var(--primary); font-size: 16px; }
.nav-toggle { display: none; background: none; border: none; font-size: 24px; cursor: pointer; color: var(--primary); }

/* ---------- Hero ---------- */
.hero {
  position: relative; min-height: 82vh; display: flex; align-items: center;
  background-size: cover; background-position: center; color: #fff;
}
.hero-mask { position: absolute; inset: 0; background: linear-gradient(120deg, rgba(10,37,64,.86), rgba(10,37,64,.45)); }
.hero-content { position: relative; z-index: 2; max-width: 800px; padding: 40px 0; }
.hero h1 { font-size: clamp(30px, 5vw, 56px); font-weight: 800; line-height: 1.2; letter-spacing: 1px; }
.hero-sub { margin: 22px 0 34px; font-size: clamp(15px, 2vw, 20px); color: #dbeafe; letter-spacing: 1px; }
.btn-primary {
  display: inline-block; background: var(--accent); color: var(--primary);
  padding: 14px 36px; border-radius: 999px; font-size: 16px; font-weight: 700;
  transition: .25s; border: none; cursor: pointer;
}
.btn-primary:hover { background: #4fe0ff; transform: translateY(-2px); }
.btn-ghost {
  display: inline-block; border: 1.5px solid var(--accent); color: var(--accent);
  padding: 11px 28px; border-radius: 999px; font-weight: 600; transition: .25s;
}
.btn-ghost:hover { background: var(--accent); color: var(--primary); }

/* ---------- Stats strip ---------- */
.stats { background: var(--bg-white); border-bottom: 1px solid var(--line); }
.stats-inner { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat { text-align: center; padding: 34px 12px; border-right: 1px solid var(--line); }
.stat:last-child { border-right: none; }
.stat .num { font-size: clamp(28px, 4vw, 40px); font-weight: 800; color: var(--gold); letter-spacing: 1px; }
.stat .lab { color: var(--ink-2); font-size: 14px; margin-top: 6px; }

/* ---------- Section ---------- */
.section { padding: 92px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; margin-bottom: 52px; }
.eyebrow { display: inline-block; font-size: 12px; letter-spacing: 4px; color: var(--accent); font-weight: 700; margin-bottom: 10px; }
.section-head h2 { font-size: clamp(26px, 3.5vw, 38px); font-weight: 800; letter-spacing: 1px; color: var(--primary); }
.section-head p { color: var(--muted); margin-top: 12px; }

/* ---------- Advantages (icon cards) ---------- */
.adv-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.adv-card {
  background: var(--bg-white); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 32px 26px; text-align: center; transition: .3s;
}
.adv-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); border-color: transparent; }
.adv-icon {
  width: 60px; height: 60px; margin: 0 auto 18px; border-radius: 50%;
  background: var(--accent-soft); color: var(--primary);
  display: flex; align-items: center; justify-content: center;
}
.adv-icon svg { width: 30px; height: 30px; }
.adv-card h3 { font-size: 18px; margin-bottom: 8px; color: var(--primary); }
.adv-card p { color: var(--ink-2); font-size: 14px; }

/* ---------- Category grid ---------- */
.cat-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.cat-card {
  background: var(--bg-white); border-radius: var(--radius); overflow: hidden; border: 1px solid var(--line);
  transition: .3s; display: flex; flex-direction: column;
}
.cat-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
.cat-card-img { aspect-ratio: 4/3; background-size: cover; background-position: center; }
.cat-card-body { padding: 20px; flex: 1; display: flex; flex-direction: column; }
.cat-card-body h3 { font-size: 19px; margin-bottom: 8px; color: var(--primary); }
.cat-card-body p { color: var(--ink-2); font-size: 14px; flex: 1; }
.cat-more { color: var(--accent); font-weight: 700; font-size: 14px; margin-top: 12px; }

/* ---------- Category detail (图文混排) ---------- */
.cat-detail { padding: 72px 0; border-top: 1px solid var(--line); }
.cat-detail-inner { display: grid; grid-template-columns: 1fr 1.25fr; gap: 50px; align-items: center; }
.cat-detail.flip .cat-detail-text { order: 2; }
.cat-detail-text h2 { font-size: clamp(24px, 3vw, 34px); margin: 8px 0 16px; font-weight: 800; color: var(--primary); }
.cat-detail-text p { color: var(--ink-2); margin-bottom: 22px; }
.cat-detail-gallery { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.g-item { aspect-ratio: 4/3; border-radius: 12px; background-size: cover; background-position: center; cursor: zoom-in; transition: .25s; }
.g-item:hover { box-shadow: var(--shadow); }

/* ---------- Cases ---------- */
.case-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.case-card { border-radius: var(--radius); overflow: hidden; position: relative; cursor: zoom-in; }
.case-img { aspect-ratio: 3/4; background-size: cover; background-position: center; transition: transform .4s; }
.case-card:hover .case-img { transform: scale(1.06); }
.case-cap { position: absolute; left: 0; right: 0; bottom: 0; padding: 14px; color: #fff;
  background: linear-gradient(transparent, rgba(10,37,64,.8)); font-weight: 600; font-size: 14px; }
.zoom-hint { position: absolute; top: 10px; right: 10px; background: rgba(10,37,64,.6);
  color: #fff; font-size: 12px; padding: 4px 10px; border-radius: 999px; opacity: 0; transition: .25s; }
.case-card:hover .zoom-hint, .g-item:hover .zoom-hint { opacity: 1; }

/* ---------- Process (numbered steps) ---------- */
.process { background: var(--bg-white); }
.proc-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 18px; position: relative; }
.proc-step { text-align: center; padding: 0 8px; position: relative; }
.proc-step .pn {
  width: 56px; height: 56px; margin: 0 auto 16px; border-radius: 50%;
  background: var(--primary); color: #fff; font-size: 20px; font-weight: 800;
  display: flex; align-items: center; justify-content: center; letter-spacing: 1px;
}
.proc-step h3 { font-size: 17px; color: var(--primary); margin-bottom: 8px; }
.proc-step p { font-size: 13px; color: var(--ink-2); }
.proc-step:not(:last-child)::after {
  content: ""; position: absolute; top: 28px; left: 56%; right: -8%; height: 2px;
  background: linear-gradient(90deg, var(--accent), transparent); opacity: .5;
}

/* ---------- About ---------- */
.about-inner { display: grid; grid-template-columns: 1.3fr 1fr; gap: 50px; align-items: center; }
.about-text h2 { font-size: clamp(24px, 3vw, 34px); margin: 8px 0 16px; font-weight: 800; color: var(--primary); }
.about-text p { color: var(--ink-2); }
.about-meta { display: grid; gap: 16px; }
.about-meta div { display: flex; justify-content: space-between; padding: 14px 18px; background: var(--bg-white); border: 1px solid var(--line); border-radius: var(--radius-sm); }
.about-meta span { color: var(--muted); }
.about-meta b { font-weight: 700; color: var(--primary); }

/* ---------- CTA band ---------- */
.cta-band { background: var(--primary); color: #fff; text-align: center; padding: 70px 0; }
.cta-band h2 { font-size: clamp(24px, 3.2vw, 36px); font-weight: 800; }
.cta-band p { color: #cbd5e1; margin: 14px 0 28px; }
.cta-band .btn-primary { background: var(--gold); color: var(--primary); }
.cta-band .btn-primary:hover { background: #ffc078; }

/* ---------- Contact ---------- */
.contact-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; }
.contact-info h2 { font-size: clamp(24px, 3vw, 34px); margin: 8px 0 12px; font-weight: 800; color: var(--primary); }
.contact-info p { color: var(--ink-2); margin-bottom: 20px; }
.contact-info ul { list-style: none; display: grid; gap: 10px; color: var(--ink-2); }
.contact-form { display: grid; gap: 14px; }
.contact-form input, .contact-form textarea {
  width: 100%; padding: 14px 16px; border: 1px solid var(--line); border-radius: var(--radius-sm);
  font-size: 15px; font-family: inherit; background: #fff; resize: vertical;
}
.contact-form input:focus, .contact-form textarea:focus { outline: none; border-color: var(--accent); }
.form-tip { font-size: 14px; color: var(--primary); min-height: 20px; }

/* ---------- Footer ---------- */
.site-footer { background: #071b2e; color: #94a3b8; padding: 56px 0 24px; }
.footer-inner { display: flex; justify-content: space-between; gap: 30px; flex-wrap: wrap; }
.footer-inner .brand-cn { color: #fff; font-size: 20px; letter-spacing: 1px; }
.footer-inner p { margin-top: 8px; color: #64748b; }
.footer-links { display: flex; gap: 24px; flex-wrap: wrap; align-items: center; }
.footer-links a:hover { color: var(--accent); }
.footer-bottom { display: flex; justify-content: space-between; margin-top: 36px; padding-top: 20px;
  border-top: 1px solid #1e3a52; font-size: 13px; color: #64748b; }
.footer-bottom a { color: var(--gold); }

/* ---------- Lightbox ---------- */
.lightbox {
  position: fixed; inset: 0; z-index: 999; background: rgba(7,27,46,.94);
  display: none; align-items: center; justify-content: center; flex-direction: column; padding: 24px;
}
.lightbox.open { display: flex; }
.lightbox img { max-width: 92vw; max-height: 80vh; border-radius: 10px; box-shadow: var(--shadow-lg); }
.lightbox .lb-cap { color: #e2e8f0; margin-top: 16px; font-size: 15px; letter-spacing: 1px; }
.lightbox .lb-close { position: absolute; top: 18px; right: 26px; color: #fff; font-size: 34px; cursor: pointer; line-height: 1; }
.lightbox .lb-nav { position: absolute; top: 50%; transform: translateY(-50%); color: #fff; font-size: 44px; cursor: pointer; user-select: none; padding: 0 18px; opacity: .65; }
.lightbox .lb-nav:hover { opacity: 1; }
.lightbox .lb-prev { left: 0; }
.lightbox .lb-next { right: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .cat-grid, .case-grid, .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .proc-grid { grid-template-columns: repeat(2, 1fr); gap: 30px; }
  .proc-step:nth-child(odd)::after { display: none; }
  .cat-detail-inner, .about-inner, .contact-inner { grid-template-columns: 1fr; gap: 30px; }
  .cat-detail.flip .cat-detail-text { order: 0; }
  .stats-inner { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(2) { border-right: none; }
  .stat:nth-child(1), .stat:nth-child(2) { border-bottom: 1px solid var(--line); }
}
@media (max-width: 640px) {
  .nav-links, .nav-phone { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open {
    display: flex; flex-direction: column; position: absolute; top: 72px; left: 0; right: 0;
    background: #fff; padding: 16px 4%; gap: 14px; border-bottom: 1px solid var(--line);
  }
  .cat-grid, .case-grid, .adv-grid { grid-template-columns: 1fr; }
  .proc-grid { grid-template-columns: 1fr; }
  .proc-step::after { display: none !important; }
  .stats-inner { grid-template-columns: 1fr; }
  .stat { border-right: none; border-bottom: 1px solid var(--line); }
  .section { padding: 60px 0; }
}