/* ============================================================
   Guansuo Precision — PVA/PFA Fittings Site
   设计值（本项目设计值，可调）：
   主色 深海蓝 #0d2b4e / 强调 青 #1fa2b8 / 品牌橙(厂牌) #f08300
   产品照为黑底，产品区使用深色卡片 #101318 与照片融合
   ============================================================ */
:root{
  --navy:#0d2b4e; --navy-deep:#081d36; --cyan:#1fa2b8; --cyan-soft:#e5f4f7;
  --orange:#f08300; --ink:#1c2733; --muted:#5b6b7a; --line:#e3e9ef;
  --bg:#ffffff; --bg-soft:#f5f8fa; --dark:#101318; --dark-2:#181c23;
  --radius:10px; --shadow:0 6px 24px rgba(13,43,78,.08);
  --max:1180px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:"Segoe UI","PingFang SC","Microsoft YaHei","Noto Sans SC",Arial,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.7;font-size:16px}
img{max-width:100%;display:block}
a{color:var(--cyan);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:var(--max);margin:0 auto;padding:0 24px}

/* ---------- header ---------- */
.topbar{background:var(--navy-deep);color:#c7d3de;font-size:13px}
.topbar .wrap{display:flex;justify-content:space-between;align-items:center;height:34px}
.topbar a{color:#c7d3de}
header.site{position:sticky;top:0;z-index:50;background:#fff;border-bottom:1px solid var(--line);transition:box-shadow .25s}
header.site.scrolled{box-shadow:0 4px 18px rgba(13,43,78,.12)}
.nav-bar{display:flex;align-items:center;gap:28px;height:72px}
.logo{display:flex;align-items:center;gap:10px;color:var(--navy);font-weight:700;font-size:19px;white-space:nowrap}
.logo:hover{text-decoration:none}
.logo .mark{width:36px;height:auto;flex:0 0 auto;object-fit:contain}
.logo small{display:block;font-size:11px;font-weight:500;color:var(--muted);letter-spacing:.14em;line-height:1.1}
nav.main{display:flex;gap:26px;margin-left:auto;align-items:center}
nav.main a{color:var(--ink);font-size:15px;font-weight:500;padding:6px 2px;border-bottom:2px solid transparent}
nav.main a:hover,nav.main a.active{color:var(--cyan);border-bottom-color:var(--cyan);text-decoration:none}
.lang-switch{border:1px solid var(--line);border-radius:20px;padding:4px 14px;font-size:13px;color:var(--muted)}
.lang-switch:hover{border-color:var(--cyan);color:var(--cyan);text-decoration:none}
.btn{display:inline-block;padding:11px 26px;border-radius:6px;font-weight:600;font-size:15px;border:1px solid transparent;cursor:pointer;transition:all .2s}
.btn:hover{text-decoration:none;transform:translateY(-1px)}
.btn-primary{background:var(--orange);color:#fff}
.btn-primary:hover{background:#d97400;color:#fff}
.btn-ghost{border-color:rgba(255,255,255,.6);color:#fff}
.btn-ghost:hover{border-color:#fff;color:#fff}
.btn-outline{border-color:var(--cyan);color:var(--cyan)}
.btn-outline:hover{background:var(--cyan);color:#fff}
.nav-toggle{display:none;margin-left:auto;background:none;border:1px solid var(--line);border-radius:6px;padding:8px 12px;font-size:18px;cursor:pointer;color:var(--navy)}

/* ---------- hero ---------- */
.hero{position:relative;color:#fff;background:var(--navy-deep);overflow:hidden}
.hero .bg{position:absolute;inset:0;background-size:cover;background-position:center;opacity:.38}
.hero .veil{position:absolute;inset:0;background:linear-gradient(100deg,rgba(8,29,54,.92) 22%,rgba(8,29,54,.55) 60%,rgba(8,29,54,.25))}
.hero .wrap{position:relative;padding:96px 24px 104px;max-width:var(--max)}
.hero .kicker{display:inline-block;font-size:13px;letter-spacing:.28em;color:#8fd4e0;text-transform:uppercase;margin-bottom:18px}
.hero h1{font-size:40px;line-height:1.28;font-weight:700;max-width:720px}
.hero h1 em{font-style:normal;color:#6fc6d6}
.hero p.lead{margin-top:18px;font-size:17px;color:#c9d6e2;max-width:640px}
.hero .cta{margin-top:34px;display:flex;gap:14px;flex-wrap:wrap}
.hero-strip{background:var(--cyan-soft);border-bottom:1px solid var(--line)}
.hero-strip .wrap{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;padding:22px 24px}
.hero-strip .item b{display:block;color:var(--navy);font-size:15px}
.hero-strip .item span{font-size:13px;color:var(--muted)}

/* ---------- sections ---------- */
section.block{padding:78px 0}
section.block.soft{background:var(--bg-soft)}
.sec-head{max-width:760px;margin-bottom:44px}
.sec-head .eyebrow{color:var(--cyan);font-weight:700;font-size:13px;letter-spacing:.2em;text-transform:uppercase}
.sec-head h2{color:var(--navy);font-size:30px;margin:8px 0 14px;line-height:1.35}
.sec-head p{color:var(--muted)}

/* category cards on white */
.cat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.cat-card{background:var(--dark);border-radius:var(--radius);overflow:hidden;position:relative;transition:transform .25s,box-shadow .25s}
.cat-card:hover{transform:translateY(-4px);box-shadow:0 14px 34px rgba(8,29,54,.22)}
.cat-card img{width:100%;height:210px;object-fit:cover}
.cat-card .info{padding:18px 20px 20px;background:var(--dark-2)}
.cat-card h3{color:#fff;font-size:17px}
.cat-card h3 span{color:#8fd4e0;font-size:13px;font-weight:500;display:block;margin-top:2px;letter-spacing:.02em}
.cat-card p{color:#9aa7b4;font-size:13.5px;margin-top:8px;line-height:1.6}
.cat-card .more{color:#6fc6d6;font-size:13px;display:inline-block;margin-top:10px}

/* feature blocks */
.feat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.feat{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px 22px}
.feat .ico{width:44px;height:44px;border-radius:9px;background:var(--cyan-soft);display:flex;align-items:center;justify-content:center;margin-bottom:16px}
.feat .ico svg{width:24px;height:24px;stroke:var(--cyan);fill:none;stroke-width:1.8}
.feat h3{font-size:16px;color:var(--navy);margin-bottom:8px}
.feat p{font-size:14px;color:var(--muted)}

/* split section */
.split{display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center}
.split img{border-radius:var(--radius);box-shadow:var(--shadow)}
.split .points{margin-top:22px;display:grid;gap:14px}
.split .points li{list-style:none;padding-left:26px;position:relative;color:var(--ink);font-size:15px}
.split .points li::before{content:"";position:absolute;left:0;top:8px;width:12px;height:12px;border-radius:3px;background:var(--cyan)}
.split .points li b{color:var(--navy)}

/* dark product band (photos have black bg) */
.dark-band{background:var(--dark);color:#cfd8e0}
.dark-band .sec-head h2{color:#fff}
.dark-band .sec-head p{color:#93a1af}
.gallery{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.gallery img{width:100%;height:190px;object-fit:cover;border-radius:8px;transition:opacity .2s}
.gallery img:hover{opacity:.82}
.spec-table{width:100%;border-collapse:collapse;background:#fff;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.spec-table th,.spec-table td{padding:13px 18px;border-bottom:1px solid var(--line);text-align:left;font-size:14.5px}
.spec-table th{background:var(--navy);color:#fff;font-weight:600;white-space:nowrap}
.spec-table tr:last-child td{border-bottom:none}
.spec-table td:first-child{color:var(--navy);font-weight:600;width:180px;background:#fafcfd}
.spec-note{font-size:12.5px;color:var(--muted);margin-top:10px}

/* breadcrumbs + page hero for subpages */
.page-hero{background:linear-gradient(105deg,var(--navy-deep),var(--navy) 70%);color:#fff;padding:56px 0 46px}
.page-hero h1{font-size:32px}
.page-hero .crumb{font-size:13px;color:#9db4c9;margin-bottom:12px}
.page-hero .crumb a{color:#9db4c9}

/* product page layout */
.prod-layout{display:grid;grid-template-columns:.95fr 1.05fr;gap:48px;align-items:start}
.prod-hero-img{background:var(--dark);border-radius:var(--radius);padding:26px}
.prod-hero-img img{width:100%;height:380px;object-fit:cover;border-radius:8px}
.prod-side h2{color:var(--navy);font-size:24px;margin-bottom:14px}
.prod-side p{color:var(--muted);font-size:15.5px}
.key-feats{margin:22px 0;display:grid;gap:10px}
.key-feats li{list-style:none;position:relative;padding-left:24px;font-size:15px}
.key-feats li::before{content:"✓";position:absolute;left:0;color:var(--cyan);font-weight:700}
.side-cta{background:var(--cyan-soft);border:1px solid #cfe8ee;border-radius:var(--radius);padding:22px;margin-top:26px}
.side-cta b{color:var(--navy)}
.side-cta p{font-size:13.5px;color:var(--muted);margin:6px 0 14px}
.pager{display:flex;justify-content:space-between;gap:16px;margin-top:60px;padding-top:24px;border-top:1px solid var(--line)}
.pager a{color:var(--navy);font-weight:600;font-size:14.5px;max-width:46%}
.pager a small{display:block;color:var(--muted);font-weight:400;font-size:12px}

/* application cards */
.app-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.app-card{border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;background:#fff;transition:transform .25s,box-shadow .25s}
.app-card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
.app-card .ph{height:170px;background:linear-gradient(135deg,var(--navy),var(--cyan));display:flex;align-items:center;justify-content:center}
.app-card .ph svg{width:64px;height:64px;stroke:#fff;fill:none;stroke-width:1.4;opacity:.9}
.app-card .body{padding:20px 22px 24px}
.app-card h3{color:var(--navy);font-size:17px;margin-bottom:8px}
.app-card p{font-size:14px;color:var(--muted)}

/* cta band */
.cta-band{background:linear-gradient(105deg,var(--navy-deep),var(--navy));color:#fff;padding:64px 0}
.cta-band .wrap{display:flex;align-items:center;justify-content:space-between;gap:30px;flex-wrap:wrap}
.cta-band h2{font-size:26px}
.cta-band p{color:#b9c8d6;margin-top:8px;font-size:15px}

/* forms */
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.form-grid .full{grid-column:1/-1}
.field label{display:block;font-size:14px;font-weight:600;color:var(--navy);margin-bottom:6px}
.field label span{color:var(--orange)}
.field input,.field select,.field textarea{width:100%;padding:11px 14px;border:1px solid #ccd6df;border-radius:6px;font-size:15px;font-family:inherit;background:#fff}
.field input:focus,.field select:focus,.field textarea:focus{outline:2px solid var(--cyan);outline-offset:0;border-color:var(--cyan)}
.form-note{font-size:13px;color:var(--muted);background:var(--bg-soft);border:1px dashed #c8d4dd;border-radius:8px;padding:12px 16px;margin-top:18px}

/* contact cards */
.contact-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-bottom:50px}
.contact-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px}
.contact-card h3{color:var(--navy);font-size:15px;letter-spacing:.06em;text-transform:uppercase;margin-bottom:14px}
.contact-card p{font-size:15px;color:var(--ink)}
.contact-card .ph-todo{color:var(--orange);font-size:13px}

/* footer */
footer.site{background:var(--navy-deep);color:#93a5b5;margin-top:0}
footer.site .cols{display:grid;grid-template-columns:1.4fr 1fr 1fr 1.2fr;gap:40px;padding:56px 0 40px}
footer.site h4{color:#fff;font-size:15px;margin-bottom:16px}
footer.site a{color:#93a5b5;font-size:14px;display:block;padding:3px 0}
footer.site a:hover{color:#6fc6d6;text-decoration:none}
footer.site p{font-size:14px}
footer.site .brandline{display:flex;align-items:center;gap:10px;color:#fff;font-weight:700;font-size:17px;margin-bottom:14px}
footer.site .brandline .mark{width:34px;height:auto;border-radius:8px;background:#fff;padding:4px;object-fit:contain}
.foot-bottom{border-top:1px solid rgba(255,255,255,.08);padding:18px 0;font-size:13px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px}

/* floating inquiry */
.float-inq{position:fixed;right:22px;bottom:26px;z-index:60}
.float-inq a{display:block;background:var(--orange);color:#fff;padding:13px 20px;border-radius:30px;font-weight:600;font-size:14.5px;box-shadow:0 8px 22px rgba(240,131,0,.4)}
.float-inq a:hover{text-decoration:none;background:#d97400}

/* responsive */
@media (max-width:1020px){
  .cat-grid,.feat-grid,.app-grid,.contact-grid{grid-template-columns:repeat(2,1fr)}
  .gallery{grid-template-columns:repeat(3,1fr)}
  .hero-strip .wrap{grid-template-columns:repeat(2,1fr)}
  .split{grid-template-columns:1fr;gap:30px}
  .prod-layout{grid-template-columns:1fr}
  footer.site .cols{grid-template-columns:1fr 1fr}
}
@media (max-width:680px){
  .hero h1{font-size:29px}
  .hero .wrap{padding:66px 24px 72px}
  nav.main{display:none;position:absolute;top:72px;left:0;right:0;background:#fff;flex-direction:column;
    padding:18px 24px 26px;gap:14px;border-bottom:1px solid var(--line);box-shadow:0 16px 30px rgba(8,29,54,.15)}
  nav.main.open{display:flex}
  .nav-toggle{display:block}
  .cat-grid,.feat-grid,.app-grid,.gallery,.contact-grid{grid-template-columns:1fr}
  .gallery img{height:230px}
  .form-grid{grid-template-columns:1fr}
  footer.site .cols{grid-template-columns:1fr}
  .sec-head h2{font-size:24px}
  .spec-table th,.spec-table td{padding:10px 12px;font-size:13.5px}
  .spec-table td:first-child{width:auto}
  section.block{padding:56px 0}
}
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  .btn,.cat-card,.app-card,.float-inq a{transition:none;transform:none}
}

/* certificate section */
.cert-flex{display:grid;grid-template-columns:340px 1fr;gap:44px;align-items:start}
.cert-img{display:block;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:14px;box-shadow:var(--shadow);transition:transform .25s}
.cert-img:hover{transform:translateY(-3px)}
.cert-img img{width:100%;height:auto;border-radius:4px}
@media (max-width:680px){.cert-flex{grid-template-columns:1fr;gap:24px}.cert-img{max-width:320px}}