/* =========================================================
   Gerchamp B2B Landing Prototypes — Shared Design System
   Brand: Gerchamp / 华溯能源  (blue #1a5fb4 → green #0a8f4f)
   ========================================================= */
:root{
  --blue:#1a5fb4; --blue-d:#134a8e; --blue-l:#e8f0fb;
  --green:#0a8f4f; --green-d:#0a7342; --green-l:#e6f6ee;
  --amber:#d98324; --amber-l:#fdf0e0;
  --ink:#1f2933; --sub:#5b6770; --line:#e3e8ee; --soft:#eef3f9;
  --bg:#f6f8fb; --card:#ffffff;
  --radius:14px; --radius-s:10px;
  --shadow:0 1px 3px rgba(20,40,80,.06);
  --shadow-h:0 10px 30px rgba(20,40,80,.12);
  --maxw:1140px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;color:var(--ink);background:var(--bg);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",Roboto,Helvetica,Arial,sans-serif;
  line-height:1.7;font-size:15px;-webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 22px}
section{padding:64px 0}
.sec-alt{background:var(--card);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.sec-soft{background:var(--soft)}

/* ---------- Typography ---------- */
h1,h2,h3,h4{line-height:1.25;margin:0 0 .5em;color:var(--ink)}
.h-eyebrow{display:inline-block;font-size:13px;font-weight:700;letter-spacing:.8px;
  text-transform:uppercase;color:var(--green);margin-bottom:12px}
h2.sec-title{font-size:30px;color:var(--blue-d);text-align:center;margin-bottom:8px}
.sec-lead{text-align:center;color:var(--sub);max-width:680px;margin:0 auto 40px;font-size:16px}
h3.sub{font-size:20px;color:var(--blue-d);margin-top:34px}
.muted{color:var(--sub)}

/* ---------- Buttons ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:13px 26px;border-radius:30px;font-weight:700;font-size:15px;
  border:2px solid transparent;cursor:pointer;transition:.18s;white-space:nowrap}
.btn-primary{background:var(--blue);color:#fff}
.btn-primary:hover{background:var(--blue-d);transform:translateY(-1px);box-shadow:var(--shadow-h)}
.btn-green{background:var(--green);color:#fff}
.btn-green:hover{background:var(--green-d);transform:translateY(-1px);box-shadow:var(--shadow-h)}
.btn-ghost{background:transparent;border-color:#fff;color:#fff}
.btn-ghost:hover{background:rgba(255,255,255,.14)}
.btn-outline{background:#fff;border-color:var(--blue);color:var(--blue)}
.btn-outline:hover{background:var(--blue-l)}
.btn-lg{padding:15px 34px;font-size:16px}
.btn-block{width:100%}

/* ---------- Header ---------- */
header.site{position:sticky;top:0;z-index:40;background:rgba(255,255,255,.96);
  backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
header.site .bar{max-width:var(--maxw);margin:0 auto;padding:12px 22px;
  display:flex;align-items:center;gap:18px}
.logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:19px;color:var(--blue-d);letter-spacing:.5px}
.logo .mark{width:118px;height:30px;background:transparent url('assets/logo.png') no-repeat left center / contain;position:relative;flex:0 0 auto}
.logo .mark::after{display:none}
footer.site .logo .mark{width:118px;background-image:url('assets/logo-white.png')}
.logo small{display:block;font-size:11px;font-weight:600;color:var(--sub);letter-spacing:1px}
nav.main{margin-left:auto;display:flex;align-items:center;gap:6px}
nav.main a{font-size:14px;color:var(--sub);padding:8px 13px;border-radius:8px;font-weight:600}
nav.main a:hover{color:var(--blue);background:var(--soft)}
nav.main .btn{margin-left:8px}
.nav-toggle{display:none;margin-left:auto;background:none;border:1px solid var(--line);
  border-radius:8px;padding:8px 12px;font-size:18px;cursor:pointer}

/* ---------- Hero ---------- */
.hero{background:linear-gradient(135deg,var(--blue-d),var(--blue) 55%,var(--green));
  color:#fff;padding:78px 0 70px;position:relative;overflow:hidden}
.hero::after{content:"";position:absolute;right:-120px;top:-120px;width:420px;height:420px;
  background:radial-gradient(circle,rgba(255,255,255,.12),transparent 70%);border-radius:50%}
.hero .wrap{position:relative;z-index:1}
.hero .eyebrow{display:inline-block;background:rgba(255,255,255,.16);padding:6px 14px;
  border-radius:20px;font-size:13px;letter-spacing:.5px;margin-bottom:18px}
.hero h1{font-size:40px;line-height:1.2;margin:0 0 16px;max-width:780px}
.hero p.sub{font-size:17px;opacity:.94;max-width:680px;margin:0 0 28px}
.hero .cta-row{display:flex;flex-wrap:wrap;gap:14px;margin-bottom:30px}
.hero .trust{display:flex;flex-wrap:wrap;gap:22px;font-size:13.5px;opacity:.92}
.hero .trust span{display:inline-flex;align-items:center;gap:7px}
.hero .trust b{color:#ffd27f;font-weight:700}

/* ---------- Trust strip (logos / badges) ---------- */
.trust-strip{background:#0f2e54;color:#cfe0f4;padding:16px 0;font-size:13px}
.trust-strip .wrap{display:flex;flex-wrap:wrap;justify-content:center;gap:14px 30px;text-align:center}
.trust-strip span{white-space:nowrap}

/* ---------- Feature grid ---------- */
.grid{display:grid;gap:18px}
.g2{grid-template-columns:1fr 1fr}
.g3{grid-template-columns:repeat(3,1fr)}
.g4{grid-template-columns:repeat(4,1fr)}
@media(max-width:900px){.g3,.g4{grid-template-columns:1fr 1fr}}
@media(max-width:640px){.g2,.g3,.g4{grid-template-columns:1fr}}

.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px;box-shadow:var(--shadow);transition:.18s}
.card:hover{transform:translateY(-3px);box-shadow:var(--shadow-h)}
.card .ico{width:46px;height:46px;border-radius:12px;background:var(--blue-l);
  color:var(--blue);display:flex;align-items:center;justify-content:center;
  font-size:22px;margin-bottom:14px}
.card.green .ico{background:var(--green-l);color:var(--green)}
.card h4{margin:0 0 8px;color:var(--blue-d);font-size:17px}
.card p{margin:0;color:var(--sub);font-size:14px}

/* ---------- Pills ---------- */
.pills{display:flex;flex-wrap:wrap;gap:9px;justify-content:center}
.pill{font-size:13px;padding:7px 14px;border-radius:20px;background:var(--blue-l);
  color:var(--blue-d);font-weight:600;border:1px solid #d4e3f7}
.pill.g{background:var(--green-l);color:var(--green-d);border-color:#bfe6cf}
.pill.a{background:var(--amber-l);color:var(--amber);border-color:#f3d9b6}

/* ---------- Stat row ---------- */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin:8px 0}
@media(max-width:760px){.stats{grid-template-columns:1fr 1fr}}
.stat{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px;text-align:center}
.stat b{display:block;font-size:30px;color:var(--blue-d);line-height:1.1}
.stat span{font-size:13px;color:var(--sub)}

/* ---------- Product tier cards ---------- */
.product{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  overflow:hidden;display:flex;flex-direction:column;box-shadow:var(--shadow);transition:.18s}
.product:hover{transform:translateY(-3px);box-shadow:var(--shadow-h)}
.product .top{background:linear-gradient(135deg,var(--blue-l),var(--green-l));
  padding:20px 20px 16px;border-bottom:1px solid var(--line)}
.product .cap{font-size:26px;font-weight:800;color:var(--blue-d)}
.product .cap small{font-size:14px;font-weight:600;color:var(--sub)}
.product .pos{font-size:13px;color:var(--green-d);font-weight:700;margin-top:2px}
.product .body{padding:18px 20px;flex:1;display:flex;flex-direction:column;gap:10px}
.product ul{margin:0;padding-left:18px;font-size:13.5px;color:var(--sub)}
.product ul li{margin:3px 0}
.product .foot{padding:0 20px 20px}
.product .price-note{font-size:12.5px;color:var(--sub);text-align:center;margin-bottom:10px}

/* ---------- Process steps ---------- */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;counter-reset:step}
@media(max-width:860px){.steps{grid-template-columns:1fr 1fr}}
@media(max-width:520px){.steps{grid-template-columns:1fr}}
.step{position:relative;background:var(--card);border:1px solid var(--line);
  border-radius:var(--radius);padding:22px 20px 20px;box-shadow:var(--shadow)}
.step .num{width:38px;height:38px;border-radius:50%;background:var(--blue);color:#fff;
  display:flex;align-items:center;justify-content:center;font-weight:800;margin-bottom:12px}
.step h4{margin:0 0 6px;color:var(--blue-d);font-size:16px}
.step p{margin:0;font-size:13.5px;color:var(--sub)}

/* ---------- Split feature (factory) ---------- */
.split{display:grid;grid-template-columns:1.1fr .9fr;gap:40px;align-items:center}
@media(max-width:860px){.split{grid-template-columns:1fr;gap:24px}}
.split .visual{background:linear-gradient(135deg,#0f2e54,var(--blue-d));border-radius:var(--radius);
  min-height:300px;padding:30px;color:#cfe0f4;position:relative;overflow:hidden;
  display:flex;flex-direction:column;justify-content:center}
.split .visual .tag{font-size:12px;letter-spacing:1px;text-transform:uppercase;opacity:.8}
.split .visual .big{font-size:22px;font-weight:800;color:#fff;margin:8px 0 16px}
.split .visual ul{margin:0;padding-left:18px;font-size:14px}
.split .visual li{margin:6px 0}
.checklist{list-style:none;padding:0;margin:0}
.checklist li{position:relative;padding-left:30px;margin:10px 0;color:var(--ink)}
.checklist li::before{content:"✓";position:absolute;left:0;top:0;width:22px;height:22px;
  background:var(--green);color:#fff;border-radius:50%;display:flex;align-items:center;
  justify-content:center;font-size:13px;font-weight:700}

/* ---------- Certifications ---------- */
.certs{display:flex;flex-wrap:wrap;gap:12px;justify-content:center}
.cert{background:var(--card);border:1px solid var(--line);border-radius:10px;
  padding:12px 18px;font-weight:700;color:var(--blue-d);font-size:14px;box-shadow:var(--shadow)}

/* ---------- FAQ ---------- */
.faq{max-width:820px;margin:0 auto}
details.fq{background:var(--card);border:1px solid var(--line);border-radius:var(--radius-s);
  margin:12px 0;overflow:hidden}
details.fq summary{padding:16px 20px;font-weight:700;color:var(--blue-d);cursor:pointer;
  list-style:none;display:flex;justify-content:space-between;align-items:center;gap:12px}
details.fq summary::-webkit-details-marker{display:none}
details.fq summary::after{content:"+";font-size:22px;color:var(--blue);font-weight:400;transition:.2s}
details.fq[open] summary::after{transform:rotate(45deg)}
details.fq .ans{padding:0 20px 18px;color:var(--sub);font-size:14.5px}
details.fq[open]{box-shadow:var(--shadow-h)}

/* ---------- Inquiry form ---------- */
.inquiry{background:linear-gradient(135deg,var(--blue-d),var(--green));color:#fff}
.inquiry .wrap{display:grid;grid-template-columns:1fr 1fr;gap:44px;align-items:center}
@media(max-width:860px){.inquiry .wrap{grid-template-columns:1fr;gap:28px}}
.inquiry h2{color:#fff}
.inquiry .lead{color:rgba(255,255,255,.92);max-width:420px}
.inquiry ul{list-style:none;padding:0;margin:18px 0 0}
.inquiry ul li{display:flex;gap:10px;align-items:flex-start;margin:12px 0;font-size:15px}
.inquiry ul li b{color:#ffd27f}
form.card-form{background:#fff;border-radius:var(--radius);padding:26px;box-shadow:var(--shadow-h)}
form.card-form h3{color:var(--blue-d);margin-top:0;font-size:20px;text-align:center}
.field{margin-bottom:14px}
.field label{display:block;font-size:13px;font-weight:700;color:var(--ink);margin-bottom:6px}
.field input,.field textarea,.field select{width:100%;padding:11px 13px;border:1px solid var(--line);
  border-radius:9px;font-size:14px;font-family:inherit;color:var(--ink);background:#fbfdff}
.field input:focus,.field textarea:focus,.field select:focus{outline:none;border-color:var(--blue);
  box-shadow:0 0 0 3px var(--blue-l)}
.field textarea{resize:vertical;min-height:84px}
.form-note{font-size:12px;color:var(--sub);text-align:center;margin-top:6px}

/* ---------- CTA band ---------- */
.cta-band{background:var(--blue-d);color:#fff;text-align:center;padding:50px 0}
.cta-band h2{color:#fff;font-size:26px}
.cta-band p{color:rgba(255,255,255,.9);max-width:560px;margin:0 auto 22px}

/* ---------- Footer ---------- */
footer.site{background:#0f2e54;color:#cfe0f4;padding:48px 0 30px;font-size:14px}
footer.site .cols{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:30px}
@media(max-width:760px){footer.site .cols{grid-template-columns:1fr 1fr}}
footer.site h5{color:#fff;font-size:14px;margin:0 0 14px;letter-spacing:.5px}
footer.site a{color:#cfe0f4;display:block;margin:7px 0;font-size:13.5px}
footer.site a:hover{color:#fff}
footer.site .logo{color:#fff;margin-bottom:12px}
footer.site .bottom{border-top:1px solid #1d4474;margin-top:32px;padding-top:18px;
  font-size:12.5px;color:#9fc0e8;display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px}
footer.site .desc{font-size:13.5px;color:#aecbf0;max-width:300px;margin-top:4px}

/* ---------- Floating WhatsApp ---------- */
.wa-float{position:fixed;right:20px;bottom:20px;z-index:60;display:flex;align-items:center;gap:10px;
  background:#25D366;color:#fff;padding:13px 18px 13px 14px;border-radius:40px;
  box-shadow:0 8px 22px rgba(0,0,0,.25);font-weight:700;font-size:14.5px;transition:.18s}
.wa-float:hover{transform:translateY(-2px);box-shadow:0 12px 28px rgba(0,0,0,.3)}
.wa-float .ic{width:34px;height:34px;border-radius:50%;background:#fff;color:#25D366;
  display:flex;align-items:center;justify-content:center;font-size:20px;flex:0 0 auto}

/* ---------- Breadcrumb ---------- */
.breadcrumb{font-size:13px;color:var(--sub);padding:18px 0 0}
.breadcrumb a:hover{color:var(--blue)}
.breadcrumb span{margin:0 7px;color:var(--line)}

/* ---------- Tables (spec / compare) ---------- */
.table-wrap{overflow-x:auto;margin:14px 0;border-radius:var(--radius-s);border:1px solid var(--line)}
table.spec{width:100%;border-collapse:collapse;font-size:14px;min-width:480px}
table.spec th,table.spec td{border-bottom:1px solid var(--line);padding:11px 14px;text-align:left;vertical-align:top}
table.spec th{background:var(--soft);color:var(--blue-d);font-weight:700;width:38%}
table.spec tr:last-child td{border-bottom:none}
table.spec td b{color:var(--green-d)}

/* ---------- Application cards ---------- */
.app-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
@media(max-width:860px){.app-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.app-grid{grid-template-columns:1fr}}
.app-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:22px;box-shadow:var(--shadow);display:flex;flex-direction:column;gap:8px;transition:.18s}
.app-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-h)}
.app-card .ic{width:44px;height:44px;border-radius:12px;background:var(--green-l);color:var(--green);
  display:flex;align-items:center;justify-content:center;font-size:22px}
.app-card h4{margin:4px 0 2px;color:var(--blue-d);font-size:17px}
.app-card p{margin:0;color:var(--sub);font-size:13.5px;flex:1}
.app-card .meta{font-size:12.5px;color:var(--green-d);font-weight:700}

/* ---------- Blog / Resources ---------- */
.cat-title{font-size:18px;color:var(--blue-d);margin:30px 0 14px;display:flex;align-items:center;gap:9px}
.cat-title::before{content:"";width:6px;height:20px;border-radius:3px;background:var(--green)}
.post-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
@media(max-width:860px){.post-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.post-grid{grid-template-columns:1fr}}
.post{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);display:flex;flex-direction:column;transition:.18s}
.post:hover{transform:translateY(-3px);box-shadow:var(--shadow-h)}
.post .thumb{height:120px;background:linear-gradient(135deg,var(--blue-l),var(--green-l));
  display:flex;align-items:center;justify-content:center;font-size:30px;color:var(--blue-d)}
.post .body{padding:16px 18px;flex:1;display:flex;flex-direction:column;gap:8px}
.post .tag{font-size:11.5px;font-weight:700;color:var(--green);text-transform:uppercase;letter-spacing:.5px}
.post h4{margin:0;font-size:16px;color:var(--ink);line-height:1.35}
.post p{margin:0;color:var(--sub);font-size:13px;flex:1}
.post .more{font-size:13.5px;font-weight:700;color:var(--blue)}

/* Expandable article cards (resources.html) */
.post > summary{list-style:none;cursor:pointer;display:block}
.post > summary::-webkit-details-marker{display:none}
.post > summary:focus{outline:none}
.post[open]{border-color:var(--green);box-shadow:var(--shadow-h)}
.post[open] .more{display:none}
.post-detail{padding:2px 18px 18px;color:var(--sub);font-size:14px;line-height:1.7;
  border-top:1px solid var(--line);margin-top:2px}
.post-detail p{margin:12px 0 0}
.post-detail ul{margin:12px 0 0;padding-left:20px}
.post-detail li{margin:5px 0}
.post-detail a{color:var(--blue);font-weight:600}

/* ---------- Contact info ---------- */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:26px;align-items:start}
@media(max-width:820px){.contact-grid{grid-template-columns:1fr}}
.info-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}
.info-card h3{margin-top:0;color:var(--blue-d)}
.info-row{display:flex;gap:12px;align-items:flex-start;padding:12px 0;border-bottom:1px solid var(--line)}
.info-row:last-child{border-bottom:none}
.info-row .ic{width:38px;height:38px;border-radius:10px;background:var(--blue-l);color:var(--blue);
  display:flex;align-items:center;justify-content:center;font-size:19px;flex:0 0 auto}
.info-row .t{font-size:13px;color:var(--sub)}
.info-row .v{font-weight:700;color:var(--ink);font-size:15px}
.map-ph{height:200px;background:linear-gradient(135deg,#0f2e54,var(--blue-d));border-radius:var(--radius-s);
  display:flex;align-items:center;justify-content:center;color:#cfe0f4;font-size:14px;margin-top:16px}

/* ---------- Product detail hero ---------- */
.pd-hero{background:linear-gradient(135deg,var(--blue-d),var(--blue) 60%,var(--green));color:#fff;padding:54px 0 46px}
.pd-hero .cap{font-size:42px;font-weight:800;line-height:1.1}
.pd-hero .cap small{font-size:18px;font-weight:600;opacity:.85}
.pd-hero .pos{font-size:16px;color:#ffd27f;font-weight:700;margin:6px 0 16px}
.pd-hero .cta-row{display:flex;flex-wrap:wrap;gap:12px}

/* ---------- Quick links band ---------- */
.quick-links{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
@media(max-width:820px){.quick-links{grid-template-columns:1fr 1fr}}
.ql{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:20px;
  box-shadow:var(--shadow);transition:.18s}
.ql:hover{transform:translateY(-3px);box-shadow:var(--shadow-h)}
.ql .ic{font-size:24px;margin-bottom:8px}
.ql h4{margin:0 0 4px;color:var(--blue-d);font-size:16px}
.ql p{margin:0 0 10px;color:var(--sub);font-size:13px}

/* ---------- Real images ---------- */
.pd-img{width:100%;max-height:360px;object-fit:contain;background:var(--soft);
  border:1px solid var(--line);border-radius:var(--radius);margin-bottom:22px}
.factory-img{width:100%;border-radius:var(--radius);display:block;margin-bottom:10px}
.factory-cap{color:#cfe0f4;font-size:14px;margin:0}
.gallery{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:24px}
.gallery img{width:100%;height:200px;object-fit:cover;border-radius:var(--radius-s);
  border:1px solid var(--line);box-shadow:var(--shadow)}
@media(max-width:760px){.gallery{grid-template-columns:1fr 1fr}}

/* ---------- Responsive header ---------- */
@media(max-width:820px){
  .hero h1{font-size:30px}
  nav.main{display:none}
  .nav-toggle{display:block}
  header.site.open nav.main{display:flex;position:absolute;top:100%;left:0;right:0;
    background:#fff;flex-direction:column;align-items:stretch;padding:10px 22px 18px;
    border-bottom:1px solid var(--line);box-shadow:var(--shadow-h)}
  header.site.open nav.main a{padding:11px 8px}
  header.site.open nav.main .btn{margin:8px 0 0}
}
@media(max-width:560px){
  section{padding:46px 0}
  h2.sec-title{font-size:24px}
  .hero{padding:54px 0 48px}
}

/* ---------- Inquiry form WhatsApp feedback ---------- */
.form-feedback{margin-top:16px;display:flex;flex-direction:column;gap:12px}
.form-feedback .ok{
  background:#eafaf1;color:#0a7a43;border:1px solid #b7e8cd;
  border-radius:10px;padding:11px 14px;font-size:14px;font-weight:600}
.form-feedback .ok a{color:#0a7a43;text-decoration:underline}
.wa-preview{background:#f6f8fb;border:1px solid var(--line);border-radius:10px;padding:12px 14px}
.wa-preview .lbl{font-size:12px;color:var(--muted);margin-bottom:6px;text-transform:uppercase;letter-spacing:.4px}
.wa-preview pre{
  margin:0;white-space:pre-wrap;word-break:break-word;
  font-family:inherit;font-size:13.5px;line-height:1.55;color:var(--ink)}