:root {
  --brand: #1e3a5f;
  --brand-dark: #142a45;
  --brand-light: #e6edf5;
  --text: #2c2c2a;
  --muted: #5f5e5a;
  --line: #e8e6df;
  --bg: #faf9f6;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--text);
  line-height: 1.7;
  background: #fff;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
.container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

header { position: sticky; top: 0; z-index: 50; background: rgba(255,255,255,.92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 76px; }
.logo { display: flex; align-items: center; gap: 10px; font-size: 30px; font-weight: 700; color: var(--brand-dark); letter-spacing: .5px; }
.logo img { height: 52px; width: auto; display: block; }
.logo span { color: var(--brand); }
.nav-links { display: flex; gap: 24px; }
.nav-links a { font-size: 14px; color: var(--muted); transition: color .2s; }
.nav-links a:hover, .nav-links a.active { color: var(--brand); }
.menu-btn { display: none; background: none; border: none; font-size: 22px; cursor: pointer; color: var(--text); }

.hero { background: linear-gradient(160deg, #0d1b2a 0%, #1b2f4a 55%, #24426b 100%); color: #fff; padding: 88px 0 76px; text-align: center; }
.hero .company { font-size: 16px; letter-spacing: 3px; opacity: .85; margin-bottom: 18px; }
.hero h1 { font-size: 34px; font-weight: 700; line-height: 1.35; margin-bottom: 16px; letter-spacing: 1px; }
.hero p { font-size: 16px; opacity: .92; max-width: 640px; margin: 0 auto 32px; }
.hero .badges { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.badge { background: rgba(255,255,255,.14); border: 1px solid rgba(255,255,255,.3); padding: 8px 18px; border-radius: 30px; font-size: 14px; }
.cta { display: inline-block; margin-top: 36px; background: #fff; color: var(--brand-dark); padding: 12px 32px; border-radius: 30px; font-size: 15px; font-weight: 600; transition: transform .2s; }
.cta:hover { transform: translateY(-2px); }

section { padding: 72px 0; }
.sec-head { text-align: center; margin-bottom: 44px; }
.sec-head h2 { font-size: 28px; font-weight: 700; color: var(--text); margin-bottom: 10px; }
.sec-head .sub { color: var(--muted); font-size: 15px; }
.en { display: block; font-size: 13px; color: var(--brand); letter-spacing: 2px; text-transform: uppercase; margin-bottom: 6px; }

.about { background: var(--bg); }
.about-text { max-width: 820px; margin: 0 auto; font-size: 15px; color: var(--muted); text-align: justify; }
.about-text p + p { margin-top: 16px; }
.slogan { text-align: center; font-size: 17px; color: var(--brand); font-weight: 600; letter-spacing: 2px; margin-bottom: 28px; }

.products { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.pcard { border: 1px solid var(--line); border-radius: 14px; padding: 32px 28px; background: #fff; transition: box-shadow .25s; }
.pcard:hover { box-shadow: 0 8px 28px rgba(0,0,0,.08); }
.pcard .tag { display: inline-block; font-size: 12px; color: var(--brand); background: var(--brand-light); padding: 3px 12px; border-radius: 20px; margin-bottom: 14px; }
.pcard h3 { font-size: 22px; margin-bottom: 8px; }
.purity { font-size: 40px; font-weight: 700; color: var(--brand); line-height: 1; margin: 8px 0 4px; }
.purity small { font-size: 18px; font-weight: 500; }
.pcard p { color: var(--muted); font-size: 14px; margin: 12px 0; }
.spec { list-style: none; border-top: 1px solid var(--line); margin-top: 16px; padding-top: 16px; }
.spec li { display: flex; justify-content: space-between; font-size: 13px; padding: 6px 0; color: var(--muted); }
.spec li b { color: var(--text); font-weight: 500; }

.apps { background: var(--bg); }
.apps-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.app { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 28px 20px; text-align: center; }
.app .icon { font-size: 30px; margin-bottom: 12px; }
.app h4 { font-size: 16px; margin-bottom: 6px; }
.app p { font-size: 13px; color: var(--muted); }

.adv { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.adv-item { display: flex; gap: 16px; align-items: flex-start; padding: 22px; border-radius: 12px; background: #fff; border: 1px solid var(--line); }
.adv-item .num { flex-shrink: 0; width: 40px; height: 40px; border-radius: 50%; background: var(--brand-light); color: var(--brand); display: flex; align-items: center; justify-content: center; font-weight: 700; }
.adv-item h4 { font-size: 16px; margin-bottom: 4px; }
.adv-item p { font-size: 13px; color: var(--muted); }

.equip-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 820px; margin: 0 auto; }
.equip-grid figure { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 16px; text-align: center; margin: 0; }
.equip-grid img { max-width: 100%; height: auto; border-radius: 6px; }
.equip-grid figcaption { font-size: 13px; color: var(--muted); margin-top: 10px; }
.equip-note { text-align: center; max-width: 720px; margin: 28px auto 0; font-size: 14px; color: var(--muted); }

.nav-links a.lang { color: var(--brand); font-weight: 500; }

.contact { background: linear-gradient(160deg, #0d1b2a, #1b2f4a); color: #fff; }
.contact .sec-head h2 { color: #fff; }
.contact .sec-head .sub { color: rgba(255,255,255,.85); }
.contact-cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; margin-top: 20px; }
.ccard { background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.18); border-radius: 12px; padding: 26px; text-align: center; }
.ccard .label { font-size: 13px; opacity: .8; margin-bottom: 8px; }
.ccard .val { font-size: 18px; font-weight: 600; word-break: break-all; }
.ccard .val.small { font-size: 15px; font-weight: 500; }

footer { background: #0d1b2a; color: rgba(255,255,255,.7); padding: 32px 0; text-align: center; font-size: 13px; }
footer a { color: rgba(255,255,255,.85); }
.footer-links { margin-top: 6px; }
.footer-links a { margin: 0 10px; }

/* 子页面 */
.page-hero { background: linear-gradient(160deg, #0d1b2a, #1b2f4a); color: #fff; padding: 56px 0; text-align: center; }
.page-hero h1 { font-size: 28px; letter-spacing: 1px; }
.page-hero p { margin-top: 10px; opacity: .85; font-size: 15px; }
.detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.detail-grid figure { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 16px; text-align: center; margin: 0; }
.detail-grid img { max-width: 100%; height: auto; border-radius: 6px; }
.detail-grid figcaption { font-size: 13px; color: var(--muted); margin-top: 10px; }
.lit-wrap { max-width: 860px; margin: 0 auto; }
.lit-list { padding-left: 22px; }
.lit-list li { font-size: 14px; color: var(--muted); padding: 12px 0; border-bottom: 1px dashed var(--line); }
.lit-note { margin-top: 24px; font-size: 14px; color: var(--brand); background: var(--brand-light); padding: 14px 18px; border-radius: 8px; }
.more-products { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 8px; }
.textlink { color: var(--brand); font-weight: 600; }
.textlink:hover { text-decoration: underline; }

@media (max-width: 760px) {
  .nav-links { display: none; position: absolute; top: 76px; left: 0; right: 0; background: #fff; flex-direction: column; padding: 16px 20px; border-bottom: 1px solid var(--line); gap: 16px; }
  .nav-links.open { display: flex; }
  .menu-btn { display: block; }
  .logo { font-size: 24px; }
  .logo img { height: 40px; }
  .hero h1 { font-size: 26px; }
  .hero .company { font-size: 14px; letter-spacing: 2px; }
  .products, .adv, .contact-cards, .detail-grid, .equip-grid { grid-template-columns: 1fr; }
  .apps-grid, .more-products { grid-template-columns: repeat(2, 1fr); }
}