/* =========================================================
   Songyang New Material — English Site
   Brand: deep blue #0b2138 + eco green #10b6a8 / #21c0e8
   ========================================================= */

:root{
  --navy:#0b2138;
  --navy-2:#0e2c4a;
  --navy-soft:#16324f;
  --teal:#10b6a8;
  --teal-2:#21c0e8;
  --teal-dk:#0c8e84;
  --ink:#1c2733;
  --muted:#5d6b78;
  --line:#e3e9ef;
  --bg:#ffffff;
  --bg-soft:#f5f8fb;
  --bg-navy:#0b2138;
  --header-h:69px;
  --radius:14px;
  --shadow:0 10px 30px rgba(11,33,56,.08);
  --shadow-lg:0 18px 50px rgba(11,33,56,.14);
  --maxw:1200px;
  --font:"Noto Sans SC","Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --serif:"Noto Serif SC",Georgia,"Times New Roman",serif;
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:var(--font);
  color:var(--ink);
  background:var(--bg);
  line-height:1.7;
  font-size:16px;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:var(--teal-dk);text-decoration:none}
a:hover{color:var(--teal)}
h1,h2,h3,h4{color:var(--navy);line-height:1.25;font-weight:700}
h1{font-size:clamp(30px,4vw,46px)}
h2{font-size:clamp(24px,3vw,34px)}
h3{font-size:20px}
p{margin:0 0 1em}
.container{max-width:var(--maxw);margin:0 auto;padding:0 22px}
.section{padding:72px 0}
.section.soft{background:var(--bg-soft)}
.section.navy{background:var(--navy);color:#cfe0ee}
.section.navy h2,.section.navy h3{color:#fff}
/* Navy bands: a white card sitting inside one still needs a dark heading (else #fff on #fff) */
.section.navy .card h3{color:var(--navy)}
.eyebrow{display:inline-block;color:var(--teal);font-weight:700;letter-spacing:.12em;
  text-transform:uppercase;font-size:13px;margin-bottom:10px}
.lead{font-size:18px;color:var(--muted);max-width:760px}
.center{text-align:center}
.center .lead{margin-left:auto;margin-right:auto}

/* ---------- Header / Nav ---------- */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);
  backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:68px}
.brand{display:flex;align-items:center;gap:11px;font-weight:800;color:var(--navy);font-size:18px}
.brand .logo{width:38px;height:38px;object-fit:contain}
.brand small{display:block;font-size:11px;font-weight:600;color:var(--muted);letter-spacing:.04em}
.nav-links{display:flex;gap:26px;align-items:center}
.nav-links a{color:var(--navy);font-weight:600;font-size:15px}
.nav-links a:hover{color:var(--teal)}
.nav-links a.active{color:var(--teal)}
/* 分组：桌面端包裹层"消失"，视觉与原来完全一致 */
.nav-group,.nav-group-body{display:contents}
.nav-group-title{display:none}
.nav-cta{background:var(--teal);color:#fff!important;padding:10px 18px;border-radius:999px;
  font-weight:700;transition:.2s}
.nav-cta:hover{background:var(--teal-dk);color:#fff!important}
.nav-toggle{display:none;background:none;border:none;font-size:26px;cursor:pointer;color:var(--navy)}
@media(max-width:880px){
  .nav-links{position:absolute;top:var(--header-h);left:0;right:0;background:#fff;flex-direction:column;
    gap:0;padding:0 22px;max-height:0;overflow:hidden;border-bottom:1px solid var(--line);transition:.3s}
  .nav-links.open{max-height:640px;padding:8px 22px 18px}
  .nav-links a{padding:12px 0;border-bottom:1px solid var(--line);width:100%}
  .nav-toggle{display:block}
  /* 移动端：一级 4 项 + Company 折叠组 */
  .nav-group{display:block}
  .nav-group-body{display:block;max-height:0;overflow:hidden;transition:max-height .3s}
  .nav-group-body.open{max-height:260px}
  .nav-group-body a{padding-left:16px;color:var(--muted)}
  .nav-group-title{display:flex;align-items:center;justify-content:space-between;width:100%;
    padding:12px 0;border:0;border-bottom:1px solid var(--line);background:none;cursor:pointer;
    font-family:inherit;font-weight:600;font-size:15px;color:var(--navy);text-align:left}
  .nav-group-title .chev{width:7px;height:7px;margin-right:5px;transition:transform .25s;
    border-right:2px solid var(--muted);border-bottom:2px solid var(--muted);transform:rotate(45deg)}
  .nav-group-title[aria-expanded="true"] .chev{transform:rotate(-135deg)}
  .nav-links .nav-cta{margin-top:14px;text-align:center;border-bottom:0}
}

/* ---------- Buttons ---------- */
.btn{display:inline-block;padding:13px 26px;border-radius:999px;font-weight:700;
  font-size:15px;cursor:pointer;border:none;transition:.2s}
.btn-primary{background:var(--teal);color:#fff}
.btn-primary:hover{background:var(--teal-dk);color:#fff}
.btn-ghost{background:transparent;border:2px solid var(--teal);color:var(--teal)}
.btn-ghost:hover{background:var(--teal);color:#fff}
.btn-light{background:#fff;color:var(--navy)}
.btn-light:hover{background:var(--teal-2);color:var(--navy)}
.btn-row{display:flex;gap:14px;flex-wrap:wrap;margin-top:22px}

/* ---------- Hero ---------- */
.hero{position:relative;background:
  radial-gradient(1200px 500px at 80% -10%,rgba(33,192,232,.25),transparent 60%),
  linear-gradient(135deg,var(--navy) 0%,var(--navy-2) 60%,#0a2a44 100%);
  color:#eaf3fb;overflow:hidden}
.hero .container{display:grid;grid-template-columns:1.1fr .9fr;gap:40px;align-items:center;
  padding:84px 22px 96px}
.hero h1{color:#fff;margin-bottom:18px}
.hero .lead{color:#bcd2e4}
.hero-stats{display:grid;grid-template-columns:repeat(2,1fr);gap:18px;margin-top:30px;max-width:460px}
.stat{background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.12);
  border-radius:12px;padding:16px 18px}
.stat b{display:block;font-size:26px;color:#fff}
.stat span{font-size:13px;color:#9fbbd2}
.stat small{font-size:11px;color:#7fa3bd;display:block;margin-top:2px}
.hero-visual{position:relative}
.hero-visual svg,.hero-visual img{width:100%;height:auto;display:block;
  border-radius:14px;filter:drop-shadow(0 20px 40px rgba(0,0,0,.35))}
@media(max-width:880px){.hero .container{grid-template-columns:1fr;padding:60px 22px 70px}
  .hero-visual{display:none}}

/* ---------- Trust bar ---------- */
.trustbar{background:var(--navy-soft);color:#cfe0ee}
.trustbar .container{display:flex;flex-wrap:wrap;justify-content:space-between;gap:20px;padding:22px}
.trustbar .item{display:flex;align-items:center;gap:10px;font-size:14px}
.trustbar .item svg{width:22px;height:22px;fill:var(--teal-2)}

/* ---------- Section heading ---------- */
.sec-head{margin-bottom:42px;max-width:780px}
.sec-head.center{margin-left:auto;margin-right:auto;text-align:center}
.sec-head h2{margin-bottom:12px}

/* ---------- Cards / Grid ---------- */
.grid{display:grid;gap:24px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
.grid-5{grid-template-columns:repeat(5,1fr)}
@media(max-width:900px){.grid-3,.grid-4,.grid-5{grid-template-columns:repeat(2,1fr)}}
@media(max-width:620px){.grid-2,.grid-3,.grid-4,.grid-5{grid-template-columns:1fr}}
/* hero wide stat (full-width highlight) */
.stat.wide{grid-column:1/-1;background:linear-gradient(90deg,rgba(16,182,168,.14),rgba(33,192,232,.10));border:1px solid rgba(33,192,232,.35)}

.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:26px;box-shadow:var(--shadow);transition:.22s}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:#cfe6e2}
.card .ic{width:46px;height:46px;border-radius:12px;background:rgba(16,182,168,.12);
  display:flex;align-items:center;justify-content:center;margin-bottom:16px}
.card .ic svg{width:24px;height:24px;fill:var(--teal-dk)}
.card h3{margin-bottom:8px}
.card p{color:var(--muted);font-size:15px;margin-bottom:0}
.card .more{display:inline-block;margin-top:14px;font-weight:700;font-size:14px;color:var(--teal-dk)}

/* ---------- Product card ---------- */
.product-card{display:flex;flex-direction:column;overflow:hidden;padding:0}
.product-card .ph{aspect-ratio:1/1;background:var(--bg-soft);display:flex;align-items:center;
  justify-content:center;border-bottom:1px solid var(--line);overflow:hidden}
.product-card .ph img{width:100%;height:100%;object-fit:contain}
.product-card .ph.placeholder{background:linear-gradient(135deg,#eef4f8,#dde9f0)}
.product-card .body{padding:20px 22px 24px}
.product-card .tag{display:inline-block;font-size:12px;font-weight:700;color:var(--teal-dk);
  background:rgba(16,182,168,.12);padding:3px 10px;border-radius:999px;margin-bottom:10px}
.product-card h3{font-size:18px;margin-bottom:6px}
.product-card p{font-size:14px;color:var(--muted);margin-bottom:14px}
.product-card .price{font-size:13px;color:var(--muted)}

/* ---------- Feature list ---------- */
.feat{display:flex;gap:14px;margin-bottom:18px}
.feat .ck{flex:0 0 26px;width:26px;height:26px;border-radius:50%;background:var(--teal);
  display:flex;align-items:center;justify-content:center;margin-top:3px}
.feat .ck svg{width:14px;height:14px;fill:#fff}
.feat h4{margin-bottom:2px;font-size:16px}
.feat p{margin:0;color:var(--muted);font-size:14px}

/* ---------- Split ---------- */
.split{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center}
@media(max-width:880px){.split{grid-template-columns:1fr;gap:30px}}
.split .visual{background:linear-gradient(135deg,var(--navy),var(--navy-2));border-radius:18px;
  padding:34px;color:#cfe0ee}
.split .visual svg{width:100%;height:auto}

/* ---------- Steps ---------- */
.steps{counter-reset:step}
.step{display:flex;gap:18px;padding:20px 0;border-bottom:1px solid var(--line)}
.step:last-child{border-bottom:none}
.step .num{counter-increment:step;flex:0 0 44px;width:44px;height:44px;border-radius:50%;
  background:var(--teal);color:#fff;font-weight:800;display:flex;align-items:center;
  justify-content:center;font-size:18px}
.step .num::before{content:counter(step)}
.step h4{margin-bottom:4px}
.step p{margin:0;color:var(--muted);font-size:14px}

/* ---------- Table ---------- */
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}
table.spec{width:100%;border-collapse:collapse;font-size:14px;min-width:560px}
table.spec th,table.spec td{padding:13px 16px;text-align:left;border-bottom:1px solid var(--line)}
table.spec thead th{background:var(--navy);color:#fff;font-weight:600}
table.spec tbody tr:nth-child(even){background:var(--bg-soft)}
table.spec td:first-child{font-weight:600;color:var(--navy)}
.gallery{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:20px}
@media(max-width:900px){.gallery{grid-template-columns:repeat(2,1fr)}}
@media(max-width:560px){.gallery{grid-template-columns:1fr}}
.gallery figure{margin:0;background:#fff;border:1px solid var(--line);border-radius:14px;overflow:hidden}
.gallery img{width:100%;height:260px;object-fit:contain;display:block;background:var(--bg-soft)}
.gallery figcaption{padding:10px 12px;font-size:13px;color:var(--muted);line-height:1.4}
.gallery-group{margin:38px 0 14px;font-size:19px;color:var(--navy);line-height:1.35;
  padding-left:13px;border-left:4px solid var(--teal)}
.gallery-group:first-of-type{margin-top:6px}
.gallery-group span{display:block;font-weight:500;font-size:14px;color:var(--muted);margin-top:5px}
.gallery-note{display:block;font-weight:500;font-size:13px;color:var(--muted);margin-top:5px}

/* ---------- FAQ ---------- */
.faq-item{border:1px solid var(--line);border-radius:12px;margin-bottom:12px;overflow:hidden}
.faq-item summary{padding:16px 20px;font-weight:700;color:var(--navy);cursor:pointer;
  list-style:none;display:flex;justify-content:space-between;align-items:center}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:"+";font-size:22px;color:var(--teal);font-weight:700}
.faq-item[open] summary::after{content:"\2212"}
.faq-item .ans{padding:0 20px 18px;color:var(--muted);font-size:15px}

/* ---------- Form ---------- */
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.form-grid .full{grid-column:1/-1}
.field label{display:block;font-weight:600;font-size:14px;margin-bottom:6px;color:var(--navy)}
.field input,.field select,.field textarea{width:100%;padding:12px 14px;border:1px solid var(--line);
  border-radius:10px;font-family:inherit;font-size:15px;background:#fff;color:var(--ink)}
.field input:focus,.field select:focus,.field textarea:focus{outline:none;border-color:var(--teal);
  box-shadow:0 0 0 3px rgba(16,182,168,.15)}
.field textarea{resize:vertical;min-height:120px}
.form-note{font-size:13px;color:var(--muted);margin-top:10px}
@media(max-width:620px){.form-grid{grid-template-columns:1fr}}

/* ---------- Contact info ---------- */
.contact-info{background:var(--navy);color:#cfe0ee;border-radius:var(--radius);padding:32px}
.contact-info h3{color:#fff;margin-bottom:18px}
.contact-info .row{display:flex;gap:12px;align-items:flex-start;margin-bottom:16px;font-size:15px}
.contact-info .row svg{width:22px;height:22px;fill:var(--teal-2);flex:0 0 22px;margin-top:2px}
.contact-info a{color:#9fe3df}

/* ---------- CTA band ---------- */
.cta-band{background:linear-gradient(120deg,var(--teal),var(--teal-2));color:#fff;text-align:center;
  border-radius:18px;padding:54px 30px;margin:0 auto;max-width:var(--maxw)}
.cta-band h2{color:#fff}
.cta-band p{color:rgba(255,255,255,.92);max-width:620px;margin:0 auto 10px}
.cta-band .btn-light{margin-top:18px}

/* ---------- Footer ---------- */
.site-footer{background:var(--navy);color:#9fb6c9;padding:56px 0 26px}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:34px;margin-bottom:38px}
.site-footer h4{color:#fff;font-size:15px;margin-bottom:16px;letter-spacing:.03em}
.site-footer a{color:#9fb6c9;display:block;padding:5px 0;font-size:14px}
.site-footer a:hover{color:#fff}
.footer-brand p{font-size:14px;margin-top:14px;max-width:300px}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);padding-top:20px;
  display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;font-size:13px;color:#7d97ab}
@media(max-width:880px){.footer-grid{grid-template-columns:1fr 1fr}}
@media(max-width:520px){.footer-grid{grid-template-columns:1fr}}

/* ---------- Breadcrumb ---------- */
.crumb{font-size:13px;color:var(--muted);padding:18px 0 0}
.crumb a{color:var(--muted)}
.crumb a:hover{color:var(--teal)}

/* ---------- Reveal anim ---------- */
.reveal{opacity:0;transform:translateY(22px);transition:.6s ease}
.reveal.in{opacity:1;transform:none}
@media(prefers-reduced-motion:reduce){.reveal{opacity:1;transform:none}}

/* ---------- Badge / pill ---------- */
.pill{display:inline-block;background:rgba(16,182,168,.12);color:var(--teal-dk);
  font-weight:700;font-size:13px;padding:5px 14px;border-radius:999px;margin:3px 4px 3px 0}

/* ---------- Logo svg mark ---------- */
.logo-mark{display:inline-block}

/* ---------- Floating WhatsApp button ---------- */
.wa-float{position:fixed;right:22px;bottom:22px;z-index:120;
  width:58px;height:58px;border-radius:50%;background:#25D366;
  display:flex;align-items:center;justify-content:center;
  box-shadow:0 8px 24px rgba(11,33,56,.28);
  transition:background .2s ease,transform .2s ease}
.wa-float svg{width:31px;height:31px;fill:#fff;display:block}
.wa-float:hover{background:#1EBE57;transform:translateY(-2px)}
.wa-float:focus-visible{outline:3px solid #0b2138;outline-offset:3px}
.wa-float .wa-label{position:absolute;right:70px;bottom:14px;white-space:nowrap;
  background:var(--navy);color:#fff;font-size:13px;font-weight:700;
  padding:8px 13px;border-radius:8px;opacity:0;pointer-events:none;
  transform:translateY(4px);transition:opacity .2s ease,transform .2s ease}
.wa-float:hover .wa-label,.wa-float:focus-visible .wa-label{opacity:1;transform:none}
@media(max-width:520px){.wa-float{right:16px;bottom:16px;width:54px;height:54px}
  .wa-float svg{width:29px;height:29px}}
@media(prefers-reduced-motion:reduce){.wa-float,.wa-float .wa-label{transition:none}}

/* ── In-page anchor sub-nav (sticks directly under the header) ── */
.subnav{position:sticky;top:var(--header-h);z-index:40;background:rgba(255,255,255,.96);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);box-shadow:0 8px 20px rgba(11,33,56,.05)}
.subnav .container{display:flex;gap:8px;overflow-x:auto;padding-top:10px;padding-bottom:10px;
  scrollbar-width:none;-ms-overflow-style:none}
.subnav .container::-webkit-scrollbar{display:none}
.subnav a{flex:0 0 auto;white-space:nowrap;font-size:14px;font-weight:600;color:var(--navy);
  background:var(--bg-soft);border:1px solid var(--line);padding:7px 15px;border-radius:999px;
  transition:background .2s ease,color .2s ease,border-color .2s ease}
.subnav a:hover,.subnav a:focus-visible{background:var(--teal);border-color:var(--teal);color:#fff}
.subnav ~ section[id]{scroll-margin-top:124px}
@media(max-width:880px){
  .subnav .container{padding-top:8px;padding-bottom:8px;gap:6px}
  .subnav a{font-size:13px;padding:6px 12px}
  .subnav ~ section[id]{scroll-margin-top:118px}
}

/* ── Grade panels (caution-tape.html #grades, reuses .faq-item accordion look) ── */
.grade-panel{scroll-margin-top:124px;margin-top:14px}
.grade-panel .panel-body{padding:20px}
@media(max-width:880px){.grade-panel{scroll-margin-top:118px}}
/* two-up gallery row (packing photos) */
.gallery-2{grid-template-columns:repeat(2,1fr)}
@media(max-width:620px){.gallery-2{grid-template-columns:1fr}}