:root {
  --blue: #1266de;
  --blue-dark: #0e4faf;
  --cyan: #2bd1f2;
  --navy: #0a2342;
  --navy-2: #0d2f5a;
  --ink: #1c2b3a;
  --muted: #5b6b7c;
  --bg: #ffffff;
  --bg-soft: #f4f8fd;
  --line: #e3eaf3;
  --radius: 14px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", "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 { text-decoration: none; color: inherit; }
ul { list-style: none; }

.container { max-width: 1120px; 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 { display: flex; align-items: center; gap: 28px; height: 68px; }
.brand { display: flex; align-items: center; gap: 12px; }
.brand img { height: 44px; width: auto; }
.brand-name { font-size: 17px; font-weight: 600; color: var(--navy); line-height: 1.25; }
.brand-name small { display: block; font-size: 11px; font-weight: 400; color: var(--muted); letter-spacing: .04em; }
.main-nav { display: flex; gap: 4px; margin-left: auto; align-items: center; }
.main-nav a {
  padding: 8px 14px; border-radius: 8px; font-size: 15px; color: var(--ink);
  transition: background .2s, color .2s;
}
.main-nav a:hover { background: var(--bg-soft); color: var(--blue); }
.lang-switch {
  margin-left: 8px; font-size: 13px; padding: 6px 12px; border: 1px solid var(--line);
  border-radius: 999px; color: var(--blue); font-weight: 500; white-space: nowrap;
}
.lang-switch:hover { border-color: var(--blue); background: var(--bg-soft); }

.nav-toggle { display: none; margin-left: auto; background: none; border: 1px solid var(--line); border-radius: 8px; padding: 8px 10px; cursor: pointer; }
.nav-toggle span { display: block; width: 18px; height: 2px; background: var(--navy); margin: 4px 0; border-radius: 2px; }

/* ===== hero ===== */
.hero {
  background: linear-gradient(135deg, #0a2342 0%, #0d3a77 55%, #1266de 100%);
  color: #fff;
  padding: 96px 0 0;
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: ""; position: absolute; right: -140px; top: -140px;
  width: 460px; height: 460px; border-radius: 50%;
  background: radial-gradient(circle, rgba(43, 209, 242, .28), transparent 65%);
}
.hero-inner { position: relative; z-index: 1; max-width: 780px; }
.hero-tag {
  display: inline-block; padding: 6px 16px; border: 1px solid rgba(255,255,255,.35);
  border-radius: 999px; font-size: 14px; letter-spacing: .06em; margin-bottom: 22px;
  color: #bfe3ff; background: rgba(255,255,255,.08);
}
.hero h1 { font-size: 42px; line-height: 1.3; font-weight: 700; letter-spacing: .01em; }
.hero h1 em { font-style: normal; color: var(--cyan); }
.hero p.sub { margin-top: 18px; font-size: 18px; color: #cfe0f5; max-width: 620px; }
.hero-actions { margin-top: 34px; display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 13px 30px; border-radius: 10px; font-size: 16px; font-weight: 500;
  transition: transform .15s, box-shadow .2s, background .2s;
}
.btn-primary { background: var(--cyan); color: #06263f; }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(43,209,242,.35); }
.btn-ghost { border: 1px solid rgba(255,255,255,.5); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.12); transform: translateY(-2px); }

.hero-stats {
  margin-top: 64px; display: grid; grid-template-columns: repeat(4, 1fr);
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.14);
  border-radius: var(--radius) var(--radius) 0 0; border-bottom: none;
  backdrop-filter: blur(4px);
}
.hero-stats .stat { padding: 22px 12px; text-align: center; border-left: 1px solid rgba(255,255,255,.12); }
.hero-stats .stat:first-child { border-left: none; }
.stat b { display: block; font-size: 30px; font-weight: 700; color: #fff; }
.stat b small { font-size: 15px; font-weight: 500; margin-left: 2px; }
.stat span { font-size: 13px; color: #a9c6e8; }

/* ===== sections ===== */
section.block { padding: 84px 0; }
section.block.soft { background: var(--bg-soft); }
.sec-head { text-align: center; max-width: 640px; margin: 0 auto 52px; }
.sec-head .kicker {
  color: var(--blue); font-size: 14px; font-weight: 600; letter-spacing: .18em;
  text-transform: uppercase;
}
.sec-head h2 { font-size: 32px; color: var(--navy); margin-top: 10px; line-height: 1.35; }
.sec-head p { color: var(--muted); margin-top: 12px; font-size: 16px; }

/* services */
.stage-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px 24px; transition: transform .2s, box-shadow .25s;
}
.card:hover { transform: translateY(-5px); box-shadow: 0 16px 36px rgba(13, 47, 90, .10); }
.card .num {
  width: 42px; height: 42px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, var(--blue), var(--cyan)); color: #fff; font-weight: 700; font-size: 17px;
  margin-bottom: 18px;
}
.card h3 { font-size: 18px; color: var(--navy); margin-bottom: 10px; }
.card p, .card li { font-size: 14.5px; color: var(--muted); }
.card ul { margin-top: 6px; }
.card ul li { padding-left: 16px; position: relative; margin: 5px 0; }
.card ul li::before {
  content: ""; position: absolute; left: 0; top: 10px; width: 6px; height: 6px;
  border-radius: 50%; background: var(--cyan);
}
.card .hl { color: var(--blue); font-weight: 600; }

.eng-support { margin-top: 46px; background: linear-gradient(135deg, #0a2342, #123f80); border-radius: var(--radius); padding: 40px 42px; color: #fff; }
.eng-support h3 { font-size: 20px; margin-bottom: 6px; }
.eng-support .tip { color: #9fc3ea; font-size: 14px; margin-bottom: 22px; }
.eng-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 14px; }
.eng-grid .item { background: rgba(255,255,255,.07); border: 1px solid rgba(255,255,255,.13); border-radius: 10px; padding: 16px 14px; }
.eng-grid .item b { display: block; font-size: 14.5px; margin-bottom: 6px; color: #7fd8f5; }
.eng-grid .item span { font-size: 13px; color: #c9dbf2; line-height: 1.55; display: block; }

/* quality */
.quality-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.q-card { display: flex; gap: 18px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 28px; }
.q-card .icon {
  flex: 0 0 52px; width: 52px; height: 52px; border-radius: 14px;
  background: var(--bg-soft); display: flex; align-items: center; justify-content: center;
}
.q-card .icon svg { width: 26px; height: 26px; }
.q-card h3 { font-size: 17px; color: var(--navy); margin-bottom: 6px; }
.q-card p { font-size: 14.5px; color: var(--muted); }
.q-chain { margin-top: 40px; text-align: center; }
.q-chain .chain-label { font-size: 15px; color: var(--muted); margin-bottom: 16px; }
.chain { display: inline-flex; align-items: center; flex-wrap: wrap; justify-content: center; gap: 8px; }
.chain .node {
  background: #fff; border: 1.5px solid var(--blue); color: var(--blue);
  font-weight: 600; font-size: 15px; border-radius: 10px; padding: 10px 22px;
}
.chain .arrow { color: var(--cyan); font-size: 20px; font-weight: 700; }
.chain .node.full { background: linear-gradient(135deg, var(--blue), var(--cyan)); color: #fff; border: none; }

/* supply chain */
.supply-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.supply-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px; display: flex; align-items: center; gap: 18px;
  transition: transform .2s, box-shadow .25s;
}
.supply-card:hover { transform: translateY(-4px); box-shadow: 0 14px 30px rgba(13,47,90,.10); }
.supply-card .badge {
  flex: 0 0 54px; width: 54px; height: 54px; border-radius: 13px;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 17px; color: #fff;
  background: linear-gradient(135deg, var(--blue), var(--blue-dark));
}
.supply-card:nth-child(odd) .badge { background: linear-gradient(135deg, #1787c9, var(--cyan)); }
.supply-card b { display: block; font-size: 16.5px; color: var(--navy); }
.supply-card span { font-size: 13px; color: var(--muted); }
.supply-note { text-align: center; margin-top: 26px; font-size: 13.5px; color: var(--muted); }

/* about */
.about-wrap { display: grid; grid-template-columns: 1.2fr .8fr; gap: 44px; align-items: start; }
.about-text h3 { font-size: 20px; color: var(--navy); margin: 26px 0 10px; }
.about-text h3:first-child { margin-top: 0; }
.about-text p { font-size: 15.5px; color: var(--muted); }
.culture-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.culture-card { background: var(--bg-soft); border: 1px solid var(--line); border-radius: 12px; padding: 20px 18px; }
.culture-card b { display: block; color: var(--blue); font-size: 14px; margin-bottom: 8px; letter-spacing: .04em; }
.culture-card span { font-size: 14px; color: var(--ink); line-height: 1.6; display: block; }

/* contact */
.contact-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.contact-list li { display: flex; gap: 16px; margin-bottom: 24px; align-items: flex-start; }
.contact-list .icon {
  flex: 0 0 46px; width: 46px; height: 46px; border-radius: 12px; background: var(--bg-soft);
  display: flex; align-items: center; justify-content: center;
}
.contact-list .icon svg { width: 22px; height: 22px; }
.contact-list b { display: block; font-size: 15px; color: var(--navy); margin-bottom: 3px; }
.contact-list p { font-size: 15px; color: var(--muted); }
.contact-form { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 32px; }
.contact-form h3 { font-size: 19px; color: var(--navy); margin-bottom: 18px; }
.contact-form label { display: block; font-size: 14px; color: var(--ink); margin: 14px 0 6px; font-weight: 500; }
.contact-form input, .contact-form textarea {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 15px; font-family: inherit; color: var(--ink); background: var(--bg-soft);
  transition: border-color .2s, background .2s;
}
.contact-form input:focus, .contact-form textarea:focus {
  outline: none; border-color: var(--blue); background: #fff;
}
.contact-form .btn { width: 100%; margin-top: 22px; text-align: center; border: none; cursor: pointer; }
.form-tip { margin-top: 12px; font-size: 13px; color: var(--muted); text-align: center; }

/* footer */
.site-footer { background: var(--navy); color: #9db6d4; padding: 44px 0 30px; margin-top: 20px; }
.footer-inner { display: flex; justify-content: space-between; gap: 30px; flex-wrap: wrap; align-items: flex-start; }
.footer-brand { display: flex; align-items: center; gap: 12px; color: #fff; }
.footer-brand img { height: 40px; }
.footer-brand div b { font-size: 16px; display: block; }
.footer-brand div span { font-size: 12px; color: #7f9cc0; }
.footer-info { font-size: 13.5px; line-height: 2; }
.footer-info a { color: #bfe3ff; }
.footer-copy { border-top: 1px solid rgba(255,255,255,.12); margin-top: 30px; padding-top: 20px; text-align: center; font-size: 13px; color: #7f9cc0; }

/* to top */
#toTop {
  position: fixed; right: 26px; bottom: 30px; width: 46px; height: 46px; border-radius: 50%;
  background: var(--blue); color: #fff; border: none; font-size: 20px; cursor: pointer;
  opacity: 0; pointer-events: none; transition: opacity .25s, transform .2s; z-index: 90;
  box-shadow: 0 8px 20px rgba(18,102,222,.35);
}
#toTop.show { opacity: 1; pointer-events: auto; }
#toTop:hover { transform: translateY(-3px); }

/* reveal animation */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .6s ease, transform .6s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ===== responsive ===== */
@media (max-width: 960px) {
  .hero h1 { font-size: 32px; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .hero-stats .stat:nth-child(3) { border-left: none; }
  .hero-stats .stat:nth-child(n+3) { border-top: 1px solid rgba(255,255,255,.12); }
  .stage-grid { grid-template-columns: repeat(2, 1fr); }
  .eng-grid { grid-template-columns: repeat(2, 1fr); }
  .supply-grid { grid-template-columns: repeat(2, 1fr); }
  .about-wrap, .contact-wrap { grid-template-columns: 1fr; }
  .quality-grid { grid-template-columns: 1fr; }

  .nav-toggle { display: block; }
  .main-nav {
    display: none; position: absolute; top: 68px; left: 0; right: 0;
    background: #fff; flex-direction: column; align-items: stretch;
    padding: 12px 20px 18px; border-bottom: 1px solid var(--line); gap: 6px;
  }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 12px 10px; }
  .lang-switch { margin: 8px 10px 0; text-align: center; }
  .header-inner { position: relative; }
}
@media (max-width: 560px) {
  .hero { padding-top: 68px; }
  .hero h1 { font-size: 26px; }
  .hero p.sub { font-size: 15.5px; }
  .stage-grid, .eng-grid, .supply-grid, .culture-grid { grid-template-columns: 1fr; }
  section.block { padding: 60px 0; }
  .sec-head h2 { font-size: 25px; }
  .eng-support { padding: 28px 22px; }
  .brand-name { font-size: 15px; }
  .stat b { font-size: 24px; }
}