/* GONGDA ZHONGJIE — English site prototype
   Shared stylesheet. Industrial B2B, clean, technical.
   Brand: navy #082442 / blue #17558f / teal #4fd1c7 */

:root{
  --navy:#082442;
  --blue:#17558f;
  --blue2:#2a6fb8;
  --teal:#4fd1c7;
  --teal-d:#0f9d8f;
  --ink:#16202e;
  --muted:#5b6878;
  --line:#e2e8f0;
  --bg:#f7f9fc;
  --card:#ffffff;
  --warn:#b45309;
  --warnbg:#fff7ed;
  --warnline:#fed7aa;
  --maxw:1080px;
}

*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  background:var(--bg);
  color:var(--ink);
  line-height:1.72;
  font-size:16.5px;
  -webkit-font-smoothing:antialiased;
}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 22px;}

/* ---------- header / nav ---------- */
.site-head{
  background:var(--navy);
  color:#fff;
  position:sticky;top:0;z-index:50;
  border-bottom:1px solid rgba(255,255,255,.1);
}
.site-head .wrap{display:flex;align-items:center;justify-content:space-between;
  gap:20px;min-height:64px;flex-wrap:wrap;}
.brand{display:flex;align-items:center;gap:11px;text-decoration:none;color:#fff;}
.brand .mark{
  width:34px;height:34px;border-radius:8px;flex:0 0 34px;
  background:linear-gradient(135deg,var(--teal),var(--blue2));
  display:flex;align-items:center;justify-content:center;
  font-weight:800;font-size:14px;letter-spacing:.02em;color:#06203a;
}
.brand .nm{font-weight:700;font-size:15.5px;letter-spacing:.03em;line-height:1.25;}
.brand .nm small{display:block;font-weight:400;font-size:11.5px;
  color:#9fbcd8;letter-spacing:.06em;margin-top:1px;}
nav.main{display:flex;gap:19px;flex-wrap:wrap;}
nav.main a{
  color:#c3d6ec;text-decoration:none;font-size:14px;font-weight:500;
  padding:6px 0;border-bottom:2px solid transparent;transition:.15s;
}
@media(max-width:1180px){.brand .nm small{display:none;}}
nav.main a:hover{color:#fff;border-bottom-color:var(--teal);}
nav.main a.on{color:#fff;border-bottom-color:var(--teal);}

/* ---------- hero ---------- */
.hero{
  background:linear-gradient(140deg,#082442 0%,#123f6d 52%,#1d5f9e 100%);
  color:#fff;padding:74px 0 66px;position:relative;overflow:hidden;
}
.hero::after{
  content:"";position:absolute;right:-140px;top:-120px;width:460px;height:460px;
  border-radius:50%;background:radial-gradient(circle,rgba(79,209,197,.16),transparent 68%);
}
.hero .wrap{position:relative;z-index:1;}
.eyebrow{
  display:inline-block;font-size:12px;letter-spacing:.16em;text-transform:uppercase;
  color:var(--teal);border:1px solid rgba(79,209,197,.45);
  border-radius:999px;padding:4px 14px;margin-bottom:20px;
}
.hero h1{margin:0 0 18px;font-size:38px;line-height:1.24;font-weight:700;letter-spacing:-.015em;}
.hero h1 em{font-style:normal;color:var(--teal);}
.hero .sub{font-size:18px;color:#c3d6ec;max-width:660px;margin:0 0 30px;}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;}

.btn{
  display:inline-block;text-decoration:none;font-weight:600;font-size:15px;
  padding:12px 24px;border-radius:8px;transition:.16s;border:1px solid transparent;
}
.btn-p{background:var(--teal);color:#06233c;}
.btn-p:hover{background:#6ee7db;}
.btn-g{border-color:rgba(255,255,255,.35);color:#fff;}
.btn-g:hover{background:rgba(255,255,255,.1);}

/* ---------- generic ---------- */
main{padding:0 0 80px;}
section{padding:56px 0;}
section.tight{padding:38px 0;}
h2{font-size:27px;line-height:1.32;margin:0 0 16px;font-weight:700;letter-spacing:-.01em;}
h3{font-size:19px;margin:0 0 10px;font-weight:650;}
h4{font-size:16px;margin:22px 0 8px;font-weight:650;color:var(--blue);}
p{margin:0 0 15px;}
.lead-p{font-size:18px;color:#33445a;}
.muted{color:var(--muted);font-size:14.5px;}
a.link{color:var(--blue2);text-decoration:none;border-bottom:1px solid rgba(42,111,184,.3);}
a.link:hover{border-bottom-color:var(--blue2);}
.sect-label{
  font-size:12px;letter-spacing:.16em;text-transform:uppercase;
  color:var(--teal-d);font-weight:700;margin-bottom:10px;
}

/* ---------- cards ---------- */
.grid{display:grid;gap:20px;}
.g3{grid-template-columns:repeat(3,1fr);}
.g2{grid-template-columns:repeat(2,1fr);}
@media(max-width:880px){.g3,.g2{grid-template-columns:1fr;}}

.card{
  background:var(--card);border:1px solid var(--line);border-radius:12px;
  padding:26px 26px 24px;display:flex;flex-direction:column;
}
.card .tag{
  display:inline-block;font-size:11.5px;font-weight:700;letter-spacing:.08em;
  text-transform:uppercase;color:var(--blue2);background:#eef4fb;
  border-radius:5px;padding:2px 9px;margin-bottom:14px;align-self:flex-start;
}
.card h3{margin-bottom:8px;}
.card p{font-size:15px;color:#3d4c60;margin-bottom:12px;}
.card ul{margin:0 0 14px;padding-left:19px;font-size:14.5px;color:#3d4c60;}
.card li{margin-bottom:6px;}
.card .foot{margin-top:auto;padding-top:14px;border-top:1px solid var(--line);
  font-size:13.5px;color:var(--muted);}

/* ---------- citable fact block ---------- */
.fact{
  background:var(--card);border:1px solid var(--line);border-left:5px solid var(--teal);
  border-radius:0 12px 12px 0;padding:24px 28px;margin:20px 0;
}
.fact .h{
  font-size:15.5px;font-weight:700;color:var(--navy);margin:0 0 12px;
  display:flex;align-items:center;gap:9px;
}
.fact .h::before{
  content:"";width:7px;height:7px;border-radius:50%;background:var(--teal);
  flex:0 0 7px;
}
.fact p{font-size:15.5px;color:#33445a;margin:0 0 12px;}
.fact p:last-child{margin-bottom:0;}
.fact .rule{
  font-size:13.5px;color:var(--muted);font-style:italic;
  border-top:1px dashed var(--line);padding-top:11px;margin-top:14px;
}

/* ---------- table ---------- */
.tbl-wrap{overflow-x:auto;margin:20px 0;border-radius:12px;border:1px solid var(--line);}
table{width:100%;border-collapse:collapse;background:var(--card);font-size:14.8px;min-width:600px;}
th,td{padding:12px 15px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line);}
th{background:#f0f4f9;color:var(--navy);font-weight:650;font-size:13.8px;
  letter-spacing:.01em;white-space:nowrap;}
tr:last-child td{border-bottom:none;}
td b{color:var(--navy);}

/* ---------- notes ---------- */
.note{border-radius:10px;padding:18px 22px;margin:20px 0;font-size:15px;}
.note p:last-child{margin-bottom:0;}
.note .t{font-weight:700;display:block;margin-bottom:7px;}
.note.warn{background:var(--warnbg);border:1px solid var(--warnline);}
.note.warn .t{color:var(--warn);}
.note.info{background:#eef4fb;border:1px solid #cfe0f2;}
.note.info .t{color:var(--blue);}

/* ---------- cta band ---------- */
.band{
  background:linear-gradient(135deg,#0b2c4f,#17558f);color:#fff;
  border-radius:14px;padding:40px 40px;margin:44px 0 0;
}
.band h3{font-size:22px;color:#fff;margin-bottom:10px;}
.band p{color:#c3d6ec;margin-bottom:22px;max-width:620px;}

/* ---------- footer ---------- */
.site-foot{
  background:var(--navy);color:#93aecb;padding:48px 0 34px;font-size:14.2px;
}
.site-foot a{color:#c3d6ec;text-decoration:none;}
.site-foot a:hover{color:#fff;}
.foot-grid{display:grid;grid-template-columns:1.6fr 1fr .95fr 1fr;gap:30px;}
@media(max-width:980px){.foot-grid{grid-template-columns:1fr 1fr;}}
@media(max-width:880px){.foot-grid{grid-template-columns:1fr;}}
.site-foot h5{color:#fff;font-size:14px;margin:0 0 13px;font-weight:650;
  letter-spacing:.03em;}
.site-foot ul{list-style:none;padding:0;margin:0;}
.site-foot li{margin-bottom:8px;}
.foot-base{
  margin-top:36px;padding-top:20px;border-top:1px solid rgba(255,255,255,.12);
  font-size:13px;color:#7a96b4;display:flex;justify-content:space-between;
  gap:16px;flex-wrap:wrap;
}

/* ---------- misc ---------- */
.kv{display:grid;grid-template-columns:150px 1fr;gap:9px 18px;font-size:15px;}
.kv dt{color:var(--muted);}
.kv dd{margin:0;}
@media(max-width:620px){.kv{grid-template-columns:1fr;gap:2px 0;}.kv dd{margin-bottom:11px;}}

.proto-note{
  background:#1a2433;color:#c3d6ec;font-size:13px;padding:11px 22px;
  text-align:center;letter-spacing:.02em;
}
.proto-note b{color:var(--teal);}

/* ================= photos & figures (2026-10-10) ================= */
.hero.hero-photo{
  background-image:
    linear-gradient(140deg,rgba(8,36,66,.93) 0%,rgba(18,63,109,.87) 52%,rgba(29,95,158,.79) 100%),
    url("img/membrane-rack.jpg");
  background-size:cover,cover;
  background-position:center,center 38%;
}

.fig{margin:24px 0;}
.fig img{display:block;width:100%;height:auto;border-radius:12px;border:1px solid var(--line);background:#fff;}
.fig figcaption{font-size:13.5px;color:var(--muted);margin-top:10px;line-height:1.6;}
.fig-sm{max-width:540px;}

.split{display:grid;grid-template-columns:1.05fr 1fr;gap:34px;align-items:center;}
.split.rev > *:first-child{order:2;}
@media(max-width:880px){.split{grid-template-columns:1fr;gap:24px;}.split.rev > *:first-child{order:0;}}

.photo-band{position:relative;border-radius:14px;overflow:hidden;border:1px solid var(--line);margin:0;background:#fff;}
.photo-band img{display:block;width:100%;height:360px;object-fit:cover;object-position:center 55%;}
.photo-band.strip img{height:auto;}
@media(max-width:880px){.photo-band img{height:230px;}.photo-band.strip img{height:auto;}}
.photo-band .cap{
  padding:20px 26px 22px;background:#f2f6fa;border-top:1px solid var(--line);
}
.photo-band .cap b{display:block;font-size:18.5px;color:var(--navy);margin-bottom:6px;line-height:1.35;}
.photo-band .cap span{font-size:14.5px;color:var(--muted);display:block;max-width:860px;line-height:1.62;}

.gallery{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin:24px 0;}
.gallery figure{margin:0;}
.gallery img{display:block;width:100%;height:200px;object-fit:cover;border-radius:10px;border:1px solid var(--line);}
.gallery figcaption{font-size:13px;color:var(--muted);margin-top:8px;line-height:1.5;}
@media(max-width:880px){.gallery{grid-template-columns:1fr 1fr;}}

.stat-row{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin:26px 0 6px;}
.stat{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:20px 20px 18px;}
.stat b{display:block;font-size:25px;color:var(--navy);line-height:1.15;letter-spacing:-.015em;}
.stat span{font-size:13.5px;color:var(--muted);display:block;margin-top:7px;line-height:1.5;}
@media(max-width:880px){.stat-row{grid-template-columns:1fr 1fr;}}

.brand .mark-img{width:36px;height:36px;flex:0 0 36px;display:block;border-radius:50%;}

/* ---------- model code ---------- */
.code-strip{display:flex;flex-wrap:wrap;gap:9px;margin:24px 0 8px;}
.code-seg{border-radius:10px;padding:14px 16px;color:#fff;flex:1 1 128px;min-width:118px;}
.code-seg b{display:block;font-size:19px;letter-spacing:.05em;line-height:1.2;}
.code-seg span{display:block;font-size:11.5px;letter-spacing:.06em;text-transform:uppercase;opacity:.8;margin-top:3px;}
.code-seg i{display:block;font-style:normal;font-size:12.5px;line-height:1.55;margin-top:9px;color:rgba(255,255,255,.9);}
.code-strip + p.muted{margin-top:14px;}

/* ================= page head (sub-pages with a photo header) ================= */
.page-head{
  position:relative;color:#fff;padding:56px 0 46px;overflow:hidden;
  background-image:
    linear-gradient(140deg,rgba(8,36,66,.95) 0%,rgba(18,63,109,.9) 55%,rgba(29,95,158,.84) 100%),
    url("img/membrane-rack.jpg");
  background-size:cover,cover;
  background-position:center,center 45%;
}
.page-head .wrap{position:relative;z-index:1;}
.page-head h1{font-size:31px;line-height:1.28;margin:0 0 14px;font-weight:700;letter-spacing:-.01em;}
.page-head p{color:#c3d6ec;max-width:720px;margin:0;font-size:16.5px;}
.page-head .eyebrow{margin-bottom:16px;}

/* ================= diagrams ================= */
.diagram{
  background:var(--card);border:1px solid var(--line);border-radius:12px;
  padding:22px 22px 16px;margin:26px 0;
}
.diagram svg{display:block;width:100%;height:auto;}
.diagram figcaption{font-size:13.5px;color:var(--muted);margin-top:14px;line-height:1.6;}

/* ================= honour / milestone list ================= */
.honors{display:grid;gap:14px;margin:24px 0;}
.honor{
  display:grid;grid-template-columns:96px 1fr;gap:20px;align-items:start;
  background:var(--card);border:1px solid var(--line);border-radius:12px;padding:20px 24px;
}
.honor .yr{
  font-size:21px;font-weight:750;color:var(--blue2);line-height:1.2;letter-spacing:-.01em;
  border-right:2px solid #cfe0f2;padding-right:16px;
}
.honor b{display:block;font-size:16.5px;color:var(--navy);margin-bottom:6px;}
.honor p{margin:0;font-size:14.8px;color:#3d4c60;}
@media(max-width:620px){.honor{grid-template-columns:1fr;gap:8px;}
  .honor .yr{border-right:none;border-bottom:2px solid #cfe0f2;padding:0 0 8px;}}

/* ================= two-col media/text row ================= */
.media-row{
  display:grid;grid-template-columns:repeat(2,1fr);gap:14px;margin:24px 0;
}
.media-row figure{margin:0;}
.media-row img{display:block;width:100%;height:260px;object-fit:cover;border-radius:12px;border:1px solid var(--line);}
.media-row figcaption{font-size:13px;color:var(--muted);margin-top:9px;line-height:1.55;}
@media(max-width:880px){.media-row{grid-template-columns:1fr;}.media-row img{height:220px;}}

/* ================= spec strip (compact key/value row) ================= */
.spec-row{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin:22px 0;}
.spec-row .s{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:18px 20px;}
.spec-row .s b{display:block;font-size:21px;color:var(--navy);line-height:1.2;}
.spec-row .s span{display:block;font-size:13.5px;color:var(--muted);margin-top:6px;line-height:1.5;}
@media(max-width:880px){.spec-row{grid-template-columns:1fr;}}

/* ================= inline text link list ================= */
.inline-links{font-size:15px;color:var(--muted);margin:18px 0 0;}
.inline-links a{margin-right:6px;}