/* ==========================================================
   Nanhui Plastics — B2B showcase site
   Single stylesheet shared by all pages + preview.html
   ========================================================== */

:root{
  --ink:#101828;
  --ink-2:#475467;
  --ink-3:#7a8699;
  --line:#e4e7ec;
  --line-soft:#eef1f5;
  --bg:#ffffff;
  --bg-alt:#f7f9fc;
  --brand:#0b4f8a;
  --brand-dark:#083a66;
  --brand-soft:#eaf2fa;
  --accent:#12907d;
  --accent-soft:#e6f5f1;
  --warn:#b42318;
  --radius:14px;
  --shadow:0 1px 2px rgba(16,24,40,.05), 0 8px 24px -12px rgba(16,24,40,.12);
  --wrap:1180px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Inter","PingFang SC","Microsoft YaHei",sans-serif;
  font-size:16px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4{margin:0;line-height:1.25;letter-spacing:-.01em}
p{margin:0}
.wrap{width:100%;max-width:var(--wrap);margin:0 auto;padding:0 24px}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:13px 26px;border-radius:10px;border:1px solid transparent;
  font-size:15px;font-weight:600;cursor:pointer;white-space:nowrap;
  transition:transform .15s ease, background .15s ease, border-color .15s ease, color .15s ease;
}
.btn:hover{transform:translateY(-1px)}
.btn-primary{background:var(--brand);color:#fff}
.btn-primary:hover{background:var(--brand-dark)}
.btn-accent{background:var(--accent);color:#fff}
.btn-accent:hover{background:#0e7a6a}
.btn-ghost{background:transparent;color:#fff;border-color:rgba(255,255,255,.55)}
.btn-ghost:hover{background:rgba(255,255,255,.12)}
.btn-outline{background:#fff;color:var(--brand);border-color:var(--line)}
.btn-outline:hover{border-color:var(--brand);color:var(--brand-dark)}
.btn-light{background:#fff;color:var(--brand)}
.btn-sm{padding:9px 18px;font-size:14px;border-radius:8px}

/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:60;background:rgba(255,255,255,.94);
  backdrop-filter:saturate(180%) blur(10px);
  border-bottom:1px solid var(--line-soft);
}
.header-inner{display:flex;align-items:center;gap:24px;height:72px}
.brand{order:1;display:flex;align-items:center;gap:11px;font-weight:800;font-size:17px;letter-spacing:-.02em}
.brand img{height:36px;width:auto}
.brand-mark{
  width:36px;height:36px;border-radius:9px;background:var(--brand);color:#fff;
  display:flex;align-items:center;justify-content:center;font-size:18px;font-weight:800;
}
.nav{order:2;margin-left:auto;display:flex;align-items:center;gap:28px}

/* header right cluster: language switch + mobile toggle */
.header-actions{order:3;display:flex;align-items:center;gap:10px}

.lang-switch{
  display:inline-flex;align-items:center;padding:3px;border-radius:999px;
  background:#eef2f7;border:1px solid var(--line);
}
.lang-switch a{
  font-size:12.5px;font-weight:600;line-height:1;color:var(--ink-3);
  padding:6px 12px;border-radius:999px;transition:all .15s ease;white-space:nowrap;
}
.lang-switch a:hover{color:var(--brand)}
.lang-switch a.on{background:#fff;color:var(--brand);box-shadow:0 1px 3px rgba(16,24,40,.14)}
.nav a{font-size:14.5px;font-weight:500;color:var(--ink-2);transition:color .15s}
.nav a:hover{color:var(--brand)}
.nav .btn{color:#fff}
.nav .btn:hover{color:#fff}
.nav-toggle{
  display:none;background:none;border:1px solid var(--line);border-radius:8px;
  font-size:18px;padding:5px 11px;cursor:pointer;color:var(--ink);
}

/* ---------- hero ---------- */
.hero{
  position:relative;min-height:560px;display:flex;align-items:center;
  background:linear-gradient(120deg,#0b3a63 0%,#0b4f8a 55%,#12719a 100%);
  background-size:cover;background-position:center;
  color:#fff;overflow:hidden;
}
.hero::after{
  content:"";position:absolute;inset:0;
  background:linear-gradient(90deg,rgba(6,26,45,.82) 0%,rgba(6,26,45,.55) 55%,rgba(6,26,45,.28) 100%);
}
.hero-inner{position:relative;z-index:2;padding:90px 24px;max-width:820px}
.hero-kicker{
  display:inline-block;font-size:12.5px;font-weight:700;letter-spacing:.14em;
  text-transform:uppercase;color:#9fd8cc;margin-bottom:18px;
  border-left:3px solid var(--accent);padding-left:11px;
}
.hero h1{font-size:clamp(30px,4.6vw,52px);font-weight:800;letter-spacing:-.02em;max-width:16em}
.hero .lead{font-size:clamp(15px,1.6vw,18px);color:rgba(255,255,255,.86);margin-top:20px;max-width:34em}
.hero-actions{display:flex;gap:13px;margin-top:34px;flex-wrap:wrap}

/* ---------- generic section ---------- */
.section{padding:82px 0}
.section-alt{background:var(--bg-alt);border-top:1px solid var(--line-soft);border-bottom:1px solid var(--line-soft)}
.sec-head{max-width:640px;margin-bottom:42px}
.sec-eyebrow{
  font-size:12.5px;font-weight:700;letter-spacing:.14em;text-transform:uppercase;
  color:var(--accent);margin-bottom:10px;
}
.sec-head h2{font-size:clamp(24px,3vw,34px);font-weight:750}
.sec-head p{color:var(--ink-2);margin-top:12px;font-size:15.5px}

/* ---------- category cards ---------- */
.cat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.cat-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  overflow:hidden;display:flex;flex-direction:column;
  transition:box-shadow .2s ease, transform .2s ease, border-color .2s ease;
}
.cat-card:hover{box-shadow:var(--shadow);transform:translateY(-3px);border-color:#cfd8e3}
.cat-thumb{
  aspect-ratio:4/3;background:linear-gradient(135deg,#eef3f9,#e2ebf4);
  display:flex;align-items:center;justify-content:center;overflow:hidden;
  color:#9aa9bd;font-size:13px;
}
.cat-thumb img{width:100%;height:100%;object-fit:cover}
.cat-body{padding:18px 18px 20px}
.cat-body h3{font-size:16.5px;font-weight:700}
.cat-body p{font-size:13.5px;color:var(--ink-3);margin-top:7px;line-height:1.55}
.cat-link{display:inline-block;margin-top:14px;font-size:13.5px;font-weight:600;color:var(--brand)}

/* ---------- stats ---------- */
.stats{
  display:grid;grid-template-columns:repeat(4,1fr);gap:18px;
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:34px 26px;box-shadow:var(--shadow);
}
.stat{text-align:center;padding:8px 6px;border-right:1px solid var(--line-soft)}
.stat:last-child{border-right:none}
.stat strong{display:block;font-size:clamp(26px,3.4vw,38px);font-weight:800;color:var(--brand);letter-spacing:-.02em}
.stat span{display:block;margin-top:7px;font-size:13px;color:var(--ink-3);font-weight:500}

/* ---------- advantages ---------- */
.adv-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.adv{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:24px 20px;
}
.adv-icon{
  width:42px;height:42px;border-radius:11px;background:var(--brand-soft);color:var(--brand);
  display:flex;align-items:center;justify-content:center;font-weight:800;font-size:15px;
  margin-bottom:16px;
}
.adv h3{font-size:15.5px;font-weight:700}
.adv p{font-size:13.5px;color:var(--ink-3);margin-top:8px;line-height:1.6}

/* ---------- products ---------- */
.prod-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.prod-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  overflow:hidden;display:flex;flex-direction:column;
  transition:box-shadow .2s ease, transform .2s ease, border-color .2s ease;
}
.prod-card:hover{box-shadow:var(--shadow);transform:translateY(-3px);border-color:#cfd8e3}
.prod-thumb{
  aspect-ratio:1/1;background:linear-gradient(135deg,#f2f6fa,#e8eff7);
  overflow:hidden;display:flex;align-items:center;justify-content:center;
  color:#9aa9bd;font-size:12.5px;
}
.prod-thumb img{width:100%;height:100%;object-fit:cover}
.prod-body{padding:16px 16px 18px;display:flex;flex-direction:column;flex:1}
.prod-cat{font-size:11.5px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--accent)}
.prod-body h3{font-size:14.8px;font-weight:650;margin-top:6px;line-height:1.4}
.prod-specs{list-style:none;margin:11px 0 0;padding:0;font-size:12.5px;color:var(--ink-3)}
.prod-specs li{display:flex;justify-content:space-between;gap:10px;padding:3px 0;border-bottom:1px dashed var(--line-soft)}
.prod-specs li:last-child{border-bottom:none}
.prod-specs b{color:var(--ink-2);font-weight:600}
.prod-foot{margin-top:auto;padding-top:14px}
.prod-foot .btn{width:100%}

/* ---------- logos ---------- */
.logo-row{
  display:grid;grid-template-columns:repeat(6,1fr);gap:18px;align-items:center;
}
.logo-item{
  height:76px;border:1px solid var(--line);border-radius:11px;background:#fff;
  display:flex;align-items:center;justify-content:center;padding:14px;
  filter:grayscale(100%);opacity:.72;transition:all .2s ease;
}
.logo-item:hover{filter:none;opacity:1;border-color:#cfd8e3}
.logo-item img{max-height:100%;width:auto;object-fit:contain}
.logo-item .ph{font-size:12px;color:#a6b2c2}

/* ---------- factory gallery ---------- */
.factory-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.factory-item{
  display:block;aspect-ratio:4/3;overflow:hidden;border-radius:var(--radius);
  border:1px solid var(--line);background:linear-gradient(135deg,#eef3f9,#e2ebf4);
}
.factory-item img{width:100%;height:100%;object-fit:cover;transition:transform .4s ease}
.factory-item:hover img{transform:scale(1.04)}

/* ---------- CTA band ---------- */
.cta-band{
  background:linear-gradient(115deg,var(--brand-dark),var(--brand) 62%,#0f6d8f);
  color:#fff;padding:64px 0;
}
.cta-inner{display:flex;align-items:center;justify-content:space-between;gap:32px;flex-wrap:wrap}
.cta-band h2{font-size:clamp(22px,2.8vw,30px);font-weight:750;max-width:26em}
.cta-band p{color:rgba(255,255,255,.78);margin-top:10px;font-size:15px}

/* ---------- footer ---------- */
.site-footer{background:#0c1622;color:#c3ccd8;padding:64px 0 26px}
.foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1.2fr;gap:38px}
.site-footer h4{font-size:13px;letter-spacing:.12em;text-transform:uppercase;color:#8fa0b4;margin-bottom:16px}
.site-footer p{font-size:13.8px;line-height:1.7;color:#aab6c4}
.foot-links{list-style:none;margin:0;padding:0}
.foot-links li{margin-bottom:9px;font-size:13.8px}
.foot-links a{color:#c3ccd8}
.foot-links a:hover{color:#fff}
.foot-brand{display:flex;align-items:center;gap:11px;margin-bottom:16px;color:#fff;font-weight:800;font-size:16px}
.foot-bottom{
  margin-top:42px;padding-top:20px;border-top:1px solid rgba(255,255,255,.09);
  display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;
  font-size:12.5px;color:#7d8b9c;
}

/* ---------- page banner (inner pages) ---------- */
.page-banner{
  background:linear-gradient(120deg,#0b3a63,#0b4f8a);
  color:#fff;padding:62px 0 58px;
}
.page-banner h1{font-size:clamp(25px,3.4vw,38px);font-weight:800}
.page-banner p{color:rgba(255,255,255,.8);margin-top:12px;max-width:46em;font-size:15px}
.crumbs{font-size:13px;color:rgba(255,255,255,.65);margin-bottom:14px}
.crumbs a{color:rgba(255,255,255,.85)}

/* ---------- filter chips ---------- */
.chips{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:32px}
.chip{
  padding:8px 17px;border-radius:999px;border:1px solid var(--line);background:#fff;
  font-size:13.5px;font-weight:600;color:var(--ink-2);transition:all .15s ease;
}
.chip:hover{border-color:var(--brand);color:var(--brand)}
.chip.active{background:var(--brand);border-color:var(--brand);color:#fff}

/* ---------- product detail ---------- */
.detail-grid{display:grid;grid-template-columns:1.05fr 1fr;gap:52px;align-items:start}
.detail-media{
  border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
  background:linear-gradient(135deg,#f2f6fa,#e8eff7);aspect-ratio:1/1;
  display:flex;align-items:center;justify-content:center;color:#9aa9bd;
}
.detail-media img{width:100%;height:100%;object-fit:cover}
.detail-body h1{font-size:clamp(23px,2.8vw,32px);font-weight:800}
.detail-body .lead{color:var(--ink-2);margin-top:14px;font-size:15px}
.spec-table{width:100%;border-collapse:collapse;margin-top:26px;font-size:14px}
.spec-table th,.spec-table td{padding:11px 14px;text-align:left;border-bottom:1px solid var(--line-soft)}
.spec-table th{width:38%;color:var(--ink-3);font-weight:600;background:var(--bg-alt)}
.detail-actions{display:flex;gap:12px;margin-top:28px;flex-wrap:wrap}
.note-box{
  margin-top:22px;padding:14px 17px;border-radius:10px;background:var(--accent-soft);
  border-left:3px solid var(--accent);font-size:13.5px;color:#0d5c50;
}

/* ---------- forms ---------- */
.form-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:32px;box-shadow:var(--shadow);max-width:760px;
}
.field{margin-bottom:18px}
.field label{display:block;font-size:13.5px;font-weight:600;color:var(--ink-2);margin-bottom:7px}
.field input[type=text],.field input[type=email],.field input[type=number],
.field select,.field textarea{
  width:100%;padding:11px 14px;border:1px solid var(--line);border-radius:9px;
  font-size:14.5px;font-family:inherit;color:var(--ink);background:#fff;
  transition:border-color .15s, box-shadow .15s;
}
.field input:focus,.field select:focus,.field textarea:focus{
  outline:none;border-color:var(--brand);box-shadow:0 0 0 3px rgba(11,79,138,.11);
}
.field textarea{min-height:120px;resize:vertical}
.field-row{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.hint{font-size:12.5px;color:var(--ink-3);margin-top:6px}
.alert{padding:13px 17px;border-radius:10px;font-size:14px;margin-bottom:20px}
.alert-ok{background:#e7f6ef;border-left:3px solid #12907d;color:#0d5c50}
.alert-err{background:#fdecea;border-left:3px solid var(--warn);color:#7a1710}

/* ---------- empty state ---------- */
.empty{
  padding:54px 20px;text-align:center;color:var(--ink-3);
  border:1px dashed var(--line);border-radius:var(--radius);background:var(--bg-alt);
  font-size:14px;
}

/* ---------- responsive ---------- */
@media (max-width:1024px){
  .cat-grid,.prod-grid,.adv-grid{grid-template-columns:repeat(2,1fr)}
  .factory-grid{grid-template-columns:repeat(2,1fr)}
  .stats{grid-template-columns:repeat(2,1fr);gap:22px 0}
  .stat:nth-child(2){border-right:none}
  .stat:nth-child(1),.stat:nth-child(2){padding-bottom:18px;border-bottom:1px solid var(--line-soft)}
  .logo-row{grid-template-columns:repeat(3,1fr)}
  .foot-grid{grid-template-columns:1fr 1fr}
  .detail-grid{grid-template-columns:1fr;gap:32px}
}
@media (max-width:720px){
  .section{padding:56px 0}
  .nav{
    position:absolute;top:72px;left:0;right:0;background:#fff;
    flex-direction:column;align-items:stretch;gap:0;padding:10px 20px 18px;
    border-bottom:1px solid var(--line);display:none;
  }
  .nav.open{display:flex}
  .nav a{padding:11px 0;border-bottom:1px solid var(--line-soft)}
  .nav .btn{margin-top:12px}
  .nav-toggle{display:block}
  .hero{min-height:470px}
  .hero-inner{padding:64px 24px}
  .cat-grid,.prod-grid,.adv-grid{grid-template-columns:1fr}
  .factory-grid{grid-template-columns:1fr}
  .stats{grid-template-columns:1fr;gap:0}
  .stat{border-right:none;border-bottom:1px solid var(--line-soft);padding:16px 0}
  .stat:last-child{border-bottom:none}
  .logo-row{grid-template-columns:repeat(2,1fr)}
  .foot-grid{grid-template-columns:1fr;gap:26px}
  .field-row{grid-template-columns:1fr}
  .form-card{padding:22px}
  .cta-inner{flex-direction:column;align-items:flex-start}
}

/* ---------- print ---------- */
@media print{
  .site-header,.nav-toggle,.cta-band,.hero-actions{display:none!important}
  body{font-size:12pt}
}