:root{
  --blue-deep:#0b2f52;
  --blue:#1a73b8;
  --blue-bright:#29abe2;
  --cyan:#5fd0f3;
  --ink:#12202e;
  --gray:#5b6b78;
  --line:#e3e9ee;
  --bg:#ffffff;
  --bg-soft:#f4f8fb;
  --white:#fff;
  --radius:14px;
  --shadow:0 10px 30px rgba(11,47,82,.08);
  --maxw:1180px;
  font-size:16px;
}
*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  font-family:'Be Vietnam Pro',system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
  color:var(--ink);
  background:var(--bg);
  line-height:1.6;
}
body.lang-zh{
  font-family:'Noto Sans SC','Be Vietnam Pro',system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
}
img{max-width:100%;display:block;}
.container{max-width:var(--maxw);margin:0 auto;padding:0 24px;}
a{color:inherit;text-decoration:none;}
h1,h2,h3{line-height:1.2;margin:0 0 16px;font-weight:800;}
h2{font-size:clamp(1.7rem,3vw,2.4rem);}
h3{font-size:1.15rem;}
p{margin:0 0 14px;color:var(--gray);}
.eyebrow{
  color:var(--blue-bright);
  font-weight:700;
  letter-spacing:.12em;
  font-size:.78rem;
  margin-bottom:10px;
  text-transform:uppercase;
}
.center{text-align:center;margin-left:auto;margin-right:auto;}
.section-lead{max-width:640px;color:var(--gray);}
.section{padding:88px 0;}
.section.tech,.section.solutions{background:var(--bg-soft);}

/* Buttons */
.btn{
  display:inline-flex;align-items:center;justify-content:center;
  padding:14px 28px;border-radius:999px;font-weight:700;font-size:.95rem;
  border:2px solid transparent;transition:.2s ease;cursor:pointer;
}
.btn-primary{background:var(--blue-bright);color:#fff;}
.btn-primary:hover{background:var(--blue);}
.btn-outline{border-color:rgba(255,255,255,.6);color:#fff;}
.btn-outline:hover{background:rgba(255,255,255,.12);}
.btn-block{width:100%;}

/* Header */
.site-header{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.92);backdrop-filter:blur(8px);
  border-bottom:1px solid var(--line);
}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:76px;}
.logo{display:flex;align-items:center;gap:10px;font-weight:800;}
.logo-mark{
  width:38px;height:38px;border-radius:10px;
  background:linear-gradient(135deg,var(--blue-bright),var(--blue-deep));
  color:#fff;display:flex;align-items:center;justify-content:center;font-size:1.2rem;
}
.logo-text{font-size:1.05rem;letter-spacing:.02em;color:var(--blue-deep);}
.logo-text strong{color:var(--blue-bright);}
.logo-text.light{color:#fff;}
.logo-text.light strong{color:var(--cyan);}
.main-nav{display:flex;align-items:center;gap:28px;font-weight:600;font-size:.94rem;}
.main-nav a{color:var(--ink);opacity:.85;}
.main-nav a:hover{opacity:1;color:var(--blue-bright);}
.nav-cta{
  background:var(--blue-deep);color:#fff !important;padding:10px 20px;border-radius:999px;opacity:1 !important;
}
.nav-cta:hover{background:var(--blue-bright);}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:6px;}
.nav-toggle span{width:24px;height:2px;background:var(--ink);display:block;}

.lang-switch{position:relative;margin-left:8px;}
.lang-current{
  display:flex;align-items:center;gap:7px;
  background:var(--bg-soft);border:1px solid var(--line);border-radius:999px;
  padding:8px 14px;font-weight:700;font-size:.82rem;color:var(--blue-deep);
  cursor:pointer;font-family:inherit;
}
.lang-current:hover{border-color:var(--blue-bright);}
.lang-flag{font-size:1rem;line-height:1;}
.lang-caret{font-size:.7rem;color:var(--gray);transition:transform .18s ease;}
.lang-switch.open .lang-caret{transform:rotate(180deg);}

.lang-menu{
  position:absolute;top:calc(100% + 8px);right:0;
  list-style:none;margin:0;padding:6px;
  background:#fff;border:1px solid var(--line);border-radius:14px;
  box-shadow:var(--shadow);
  width:170px;max-height:0;overflow-y:auto;
  opacity:0;pointer-events:none;
  transform:translateY(-6px);
  transition:max-height .22s ease, opacity .18s ease, transform .18s ease;
  z-index:60;
}
.lang-switch.open .lang-menu{
  max-height:220px;opacity:1;pointer-events:auto;transform:translateY(0);
}
.lang-menu::-webkit-scrollbar{width:6px;}
.lang-menu::-webkit-scrollbar-thumb{background:var(--line);border-radius:6px;}
.lang-opt{
  display:flex;align-items:center;gap:9px;width:100%;
  border:none;background:transparent;text-align:left;
  padding:10px 12px;border-radius:9px;font-size:.9rem;font-weight:600;
  color:var(--ink);cursor:pointer;font-family:inherit;
}
.lang-opt:hover{background:var(--bg-soft);}
.lang-opt.active{background:var(--blue-deep);color:#fff;}

/* Hero */
.hero{position:relative;overflow:hidden;color:#fff;padding:130px 0 90px;}
.hero-bg{
  position:absolute;inset:0;z-index:-1;
  background:
    linear-gradient(90deg,rgba(6,22,44,.55) 0%,rgba(6,22,44,.25) 45%,rgba(6,22,44,0) 70%),
    url("hero.jpg") right center / cover no-repeat,
    #0b2f52;
}
.hero{padding:150px 0 110px;}
.hero-inner > *{max-width:600px;}
.hero h1{font-size:clamp(2rem,3.4vw,2.9rem);text-shadow:0 2px 18px rgba(0,0,0,.45);}
.hero .eyebrow{color:var(--cyan);text-shadow:0 1px 8px rgba(0,0,0,.5);}
.hero-sub{color:rgba(255,255,255,.92);font-size:1.05rem;text-shadow:0 1px 10px rgba(0,0,0,.5);}
.hero-actions{display:flex;gap:16px;margin:28px 0 50px;flex-wrap:wrap;}
.hero-stats{display:flex;gap:26px;flex-wrap:wrap;border-top:1px solid rgba(255,255,255,.3);padding-top:26px;}
.hero-inner > .hero-stats{max-width:620px;}
.hero-stats div{display:flex;flex-direction:column;}
.hero-stats strong{font-size:1.4rem;font-weight:800;text-shadow:0 1px 10px rgba(0,0,0,.5);}
.hero-stats span{color:rgba(255,255,255,.85);font-size:.8rem;text-shadow:0 1px 8px rgba(0,0,0,.5);}

/* Intro */
.intro-grid{display:grid;grid-template-columns:1fr 1.3fr;gap:60px;align-items:start;}
.intro-copy h2{max-width:420px;}
.link-arrow{color:var(--blue-bright);font-weight:700;}
.intro-features{display:grid;grid-template-columns:1fr 1fr;gap:22px;}
.feature-card{
  background:var(--bg-soft);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 22px;
}
.feature-icon{
  width:44px;height:44px;border-radius:10px;background:var(--blue-deep);color:#fff;
  display:flex;align-items:center;justify-content:center;font-size:1.2rem;margin-bottom:14px;
}
.feature-card h3{margin-bottom:8px;font-size:1.02rem;}
.feature-card p{font-size:.92rem;margin:0;}

/* Certs */
.cert-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:26px;margin-top:44px;}
.cert-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:30px 26px;
  box-shadow:var(--shadow);
}
.cert-badge{
  display:inline-block;background:var(--blue-bright);color:#fff;font-weight:800;
  padding:8px 16px;border-radius:8px;margin-bottom:16px;font-size:.85rem;letter-spacing:.04em;
}
.cert-card p{margin:0;font-size:.92rem;}

/* Products */
.product-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;margin-top:40px;}
.product-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
  transition:.2s ease;
}
.product-card:hover{transform:translateY(-4px);box-shadow:var(--shadow);}
.product-thumb{aspect-ratio:4/3;background-color:#dfe9f3;background-size:cover;background-position:center;}
.thumb-1{background-image:url("product-1.jpg");}
.thumb-2{background-image:url("product-2.jpg");}
.thumb-3{background-image:url("product-3.jpg");}
.thumb-4{background-image:url("product-4.jpg");}
.thumb-5{background-image:url("product-5.jpg");}
.thumb-6{background-image:url("product-6.jpg");}
.thumb-7{background-image:url("product-7.jpg");}
.thumb-8{background-image:url("product-8.jpg");}
.product-card h3{padding:18px 18px 0;margin-bottom:6px;font-size:1rem;}
.product-card p{padding:0 18px 20px;font-size:.88rem;margin:0;}

/* Tech table */
.table-wrap{overflow-x:auto;margin-top:40px;border-radius:var(--radius);border:1px solid var(--line);background:#fff;}
.spec-table{width:100%;border-collapse:collapse;font-size:.92rem;min-width:640px;}
.spec-table th{
  background:var(--blue-deep);color:#fff;text-align:left;padding:14px 18px;font-weight:700;
}
.spec-table td{padding:13px 18px;border-bottom:1px solid var(--line);}
.spec-table tr:last-child td{border-bottom:none;}
.spec-table tr:nth-child(even){background:var(--bg-soft);}

.matrix-title{margin-top:56px;font-size:1.2rem;color:var(--blue-deep);}
.matrix-table td:not(:first-child),.matrix-table th:not(:first-child){text-align:center;}
.small-table{min-width:auto;font-size:.85rem;}
.small-table th,.small-table td{padding:11px 14px;white-space:nowrap;}

.tech-split{display:grid;grid-template-columns:1fr 1fr;gap:50px;margin-top:56px;align-items:start;}
.tech-split.reverse{margin-top:40px;}
.tech-block h3{color:var(--blue-deep);}
.check-list{list-style:none;padding:0;margin:0;}
.check-list li{
  position:relative;padding-left:28px;margin-bottom:10px;color:var(--gray);font-size:.95rem;
}
.check-list li::before{
  content:"✓";position:absolute;left:0;top:0;color:var(--blue-bright);font-weight:800;
}
.coating-bars{display:flex;gap:26px;align-items:flex-end;height:120px;margin-top:20px;}
.coating-bar{display:flex;flex-direction:column;align-items:center;justify-content:flex-end;height:100%;gap:8px;}
.coating-bar span{
  width:34px;border-radius:6px 6px 0 0;background:linear-gradient(180deg,var(--blue-bright),var(--blue-deep));display:block;
}
.coating-bar label{font-size:.82rem;font-weight:700;color:var(--gray);}

/* Solutions */
.solution-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:40px;}
.solution-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 22px;font-weight:700;color:var(--blue-deep);text-align:center;
  box-shadow:var(--shadow);
}

/* Manufacturing */
.manufacturing-grid{display:grid;grid-template-columns:1.3fr 1fr;gap:60px;align-items:center;}
.manufacturing-stats{display:grid;grid-template-columns:1fr 1fr;gap:20px;}
.stat-box{
  background:linear-gradient(135deg,var(--blue-deep),var(--blue-bright));color:#fff;
  border-radius:var(--radius);padding:26px 22px;
}
.stat-box strong{display:block;font-size:1.6rem;font-weight:800;}
.stat-box span{font-size:.85rem;opacity:.85;}

/* FAQ */
.faq-list{max-width:800px;margin:40px auto 0;display:flex;flex-direction:column;gap:14px;}
.faq-list details{
  background:#fff;border:1px solid var(--line);border-radius:12px;padding:18px 22px;
}
.faq-list summary{font-weight:700;cursor:pointer;list-style:none;}
.faq-list summary::-webkit-details-marker{display:none;}
.faq-list summary::after{content:"+";float:right;color:var(--blue-bright);font-weight:800;}
.faq-list details[open] summary::after{content:"–";}
.faq-list p{margin:14px 0 0;font-size:.94rem;}

/* Contact */
.contact-grid{display:grid;grid-template-columns:1.1fr 1fr;gap:60px;}
.contact-info p{margin:6px 0;font-size:.92rem;color:var(--ink);}
.contact-form{
  background:var(--bg-soft);border:1px solid var(--line);border-radius:var(--radius);
  padding:32px;display:flex;flex-direction:column;gap:16px;
}
.contact-form label{display:flex;flex-direction:column;gap:6px;font-size:.9rem;font-weight:600;color:var(--ink);}
.contact-form input,.contact-form textarea{
  border:1px solid var(--line);border-radius:8px;padding:12px 14px;font-family:inherit;font-size:.95rem;
  background:#fff;
}
.contact-form input:focus,.contact-form textarea:focus{outline:2px solid var(--blue-bright);}
.form-note{font-size:.8rem;color:var(--gray);margin:0;}

/* Footer */
.site-footer{background:var(--blue-deep);color:rgba(255,255,255,.8);padding-top:60px;}
.footer-inner{display:grid;grid-template-columns:1fr 2fr;gap:60px;padding-bottom:40px;}
.footer-brand p{color:rgba(255,255,255,.65);margin-top:12px;font-size:.9rem;}
.footer-cols{display:grid;grid-template-columns:repeat(3,1fr);gap:30px;}
.footer-cols h4{color:#fff;margin-bottom:14px;font-size:.9rem;letter-spacing:.05em;text-transform:uppercase;}
.footer-cols a,.footer-cols span{display:block;margin-bottom:10px;font-size:.9rem;color:rgba(255,255,255,.7);}
.footer-cols a:hover{color:var(--cyan);}
.footer-bottom{border-top:1px solid rgba(255,255,255,.15);padding:20px 0;font-size:.82rem;color:rgba(255,255,255,.55);}

/* Responsive */
@media (max-width:960px){
  .intro-grid,.tech-split,.manufacturing-grid,.contact-grid{grid-template-columns:minmax(0,1fr);}
  .tech-split > *,.intro-grid > *,.manufacturing-grid > *,.contact-grid > *{min-width:0;}
  .product-grid{grid-template-columns:repeat(2,1fr);}
  .cert-grid,.solution-grid{grid-template-columns:1fr 1fr;}
  .footer-inner{grid-template-columns:1fr;}
}
@media (max-width:980px){
  .main-nav{
    position:absolute;top:76px;left:0;right:0;background:#fff;flex-direction:column;
    align-items:flex-start;padding:20px 24px;gap:16px;border-bottom:1px solid var(--line);
    display:none;
  }
  .main-nav.open{display:flex;}
  .nav-toggle{display:flex;order:3;}
  .lang-switch{order:2;margin-left:auto;}
  .header-inner{flex-wrap:wrap;}
}
@media (max-width:900px){
  .hero{padding:110px 0 80px;}
  .hero-bg{
    background:
      linear-gradient(90deg,rgba(6,22,44,.82) 0%,rgba(6,22,44,.6) 100%),
      url("hero.jpg") 72% center / cover no-repeat,
      #0b2f52;
  }
}
@media (max-width:720px){
  .product-grid{grid-template-columns:1fr 1fr;}
  .cert-grid,.solution-grid,.manufacturing-stats,.intro-features{grid-template-columns:1fr;}
  .hero-stats{gap:26px;}
}

/* ===== Mobile optimisation ===== */
.matrix-table td:first-child{position:sticky;left:0;background:#fff;z-index:1;}
.matrix-table tr:nth-child(even) td:first-child{background:var(--bg-soft);}

@media (max-width:980px){
  .nav-toggle{width:44px;height:44px;align-items:center;justify-content:center;}
  .main-nav a{padding:12px 0;width:100%;font-size:1rem;}
  .main-nav .nav-cta{width:100%;text-align:center;padding:14px 20px;margin-top:4px;}
  .lang-current{min-height:44px;}
  .lang-opt{min-height:44px;}
}

@media (max-width:720px){
  .section{padding:60px 0;}
  .container{padding:0 18px;}
  h2{font-size:1.65rem;}
  .link-arrow{display:inline-block;padding:12px 0;}
  .hero-actions{flex-direction:column;margin:24px 0 36px;}
  .hero-actions .btn{width:100%;padding:16px 24px;}
  .hero-stats{display:grid;grid-template-columns:1fr 1fr;gap:18px 20px;}
  .intro-grid{gap:36px;}
  .feature-card{padding:22px 18px;}
  .cert-card{padding:24px 20px;}
  .solution-card{padding:20px 16px;}
  .tech-split{gap:34px;margin-top:40px;}
  .matrix-title{margin-top:40px;}
  .manufacturing-stats{grid-template-columns:1fr 1fr;}
  .contact-form{padding:22px 18px;}
  .contact-form input,.contact-form textarea{font-size:16px;padding:14px;}
  .contact-form .btn{padding:16px 24px;}
  .faq-list summary{padding:6px 0;font-size:.98rem;}
  .footer-cols{grid-template-columns:1fr 1fr;gap:26px 20px;}
  .footer-cols > div:last-child{grid-column:1/-1;}
  .footer-cols a{padding:10px 0;margin-bottom:0;word-break:break-word;}
  .footer-inner{gap:34px;}
}

@media (max-width:560px){
  .product-grid{grid-template-columns:1fr;gap:14px;margin-top:28px;}
  .product-card{display:grid;grid-template-columns:118px 1fr;grid-template-rows:auto 1fr;}
  .product-card:hover{transform:none;}
  .product-thumb{grid-row:1 / span 2;aspect-ratio:auto;height:100%;min-height:132px;}
  .product-card h3{padding:14px 14px 0;font-size:.98rem;}
  .product-card p{padding:0 14px 14px;font-size:.86rem;}
  .manufacturing-stats{gap:12px;}
  .stat-box{padding:20px 16px;}
  .stat-box strong{font-size:1.35rem;}
  .small-table th,.small-table td{padding:10px 12px;}
}