/* ============================================================
   Rongsentai — new visual system
   ============================================================ */
:root{
  --bg:#ffffff;
  --bg-soft:#f4f8ff;
  --bg-softer:#eef4ff;
  --ink:#0b1220;
  --ink-2:#475569;
  --ink-3:#94a3b8;
  --brand:#2563eb;
  --brand-2:#06b6d4;
  --line:#e6ecf5;
  --line-2:#d8e2f2;
  --dark:#0a0f1e;
  --dark-2:#101a33;
  --radius:18px;
  --shadow-sm:0 4px 14px rgba(15,23,42,.06);
  --shadow:0 18px 50px rgba(15,23,42,.10);
  --shadow-lg:0 30px 70px rgba(37,99,235,.18);
  --grad:linear-gradient(120deg,#2563eb 0%,#06b6d4 100%);
  --maxw:1180px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:"PingFang SC","Microsoft YaHei","Segoe UI",system-ui,-apple-system,"Helvetica Neue",Arial,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 24px}
section{padding:96px 0}
.bg-light{background:var(--bg-soft)}

/* ---------- Buttons ---------- */
.btn{display:inline-flex;align-items:center;gap:8px;padding:14px 26px;border-radius:999px;
  font-weight:700;font-size:15px;cursor:pointer;border:1px solid transparent;transition:.25s;white-space:nowrap}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 12px 30px rgba(37,99,235,.35)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 18px 38px rgba(37,99,235,.45)}
.btn-outline{border-color:rgba(255,255,255,.4);color:#fff}
.btn-outline:hover{background:#fff;color:var(--ink);transform:translateY(-2px)}
.btn-ghost{background:var(--bg-softer);color:var(--brand);border:1px solid var(--line-2)}
.btn-ghost:hover{background:#fff;box-shadow:var(--shadow-sm)}

/* ---------- Header ---------- */
.header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.82);
  backdrop-filter:saturate(160%) blur(14px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:72px}
.logo{display:flex;align-items:center;gap:12px;font-weight:800}
.logo .mark{width:38px;height:38px;border-radius:11px;display:grid;place-items:center;
  background:var(--grad);color:#fff;font-weight:900;font-size:20px;box-shadow:var(--shadow-sm)}
.logo .mark img{width:24px;height:24px}
.logo small{display:block;font-size:11px;font-weight:600;color:var(--ink-3);letter-spacing:.4px}
.nav-links{display:flex;gap:30px;font-weight:600;font-size:15px}
.nav-links a{color:var(--ink-2);position:relative;padding:6px 0;transition:.2s}
.nav-links a:hover{color:var(--ink)}
.nav-links a.active{color:var(--brand)}
.nav-links a.active::after{content:"";position:absolute;left:0;right:0;bottom:-2px;height:3px;border-radius:3px;background:var(--grad)}
.lang-switch{display:flex;gap:6px;background:var(--bg-softer);border:1px solid var(--line);border-radius:999px;padding:4px}
.lang-switch button{border:0;background:transparent;cursor:pointer;font-weight:700;font-size:13px;
  padding:6px 12px;border-radius:999px;color:var(--ink-2);transition:.2s}
.lang-switch button.active{background:#fff;color:var(--brand);box-shadow:var(--shadow-sm)}
.menu-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer}
.menu-toggle span{width:24px;height:2.5px;background:var(--ink);border-radius:2px;transition:.3s}

/* ---------- Hero ---------- */
.hero{position:relative;overflow:hidden;background:
   radial-gradient(1200px 600px at 80% -10%,rgba(37,99,235,.35),transparent 60%),
   radial-gradient(900px 500px at 0% 110%,rgba(6,182,212,.28),transparent 55%),
   linear-gradient(160deg,#0a0f1e 0%,#101a33 60%,#0d1730 100%);color:#fff;padding:0}
.hero-grid{position:absolute;inset:0;background-image:
   linear-gradient(rgba(255,255,255,.05) 1px,transparent 1px),
   linear-gradient(90deg,rgba(255,255,255,.05) 1px,transparent 1px);
  background-size:46px 46px;mask-image:radial-gradient(white,transparent 78%);opacity:.6}
.hero .container{position:relative;z-index:2;display:grid;grid-template-columns:1.05fr .95fr;
  gap:40px;align-items:center;padding:104px 24px 110px}
.hero-copy .eyebrow{display:inline-flex;align-items:center;gap:8px;font-size:13px;font-weight:700;
  letter-spacing:.5px;color:#9fd9ff;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.18);
  padding:7px 14px;border-radius:999px;margin-bottom:22px}
.hero h1{font-size:clamp(34px,5vw,56px);line-height:1.12;font-weight:900;letter-spacing:-.5px;margin-bottom:20px}
.hero h1 .grad{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.en-title{font-size:15px;font-weight:600;color:#9fb3d6;margin-bottom:18px;letter-spacing:.3px}
.hero p.lead{font-size:18px;color:#c5d2ea;max-width:540px;margin-bottom:32px}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap}
.hero-art{position:relative}
.hero-art img{width:100%;filter:drop-shadow(0 30px 60px rgba(0,0,0,.45))}
.hero-stats{display:flex;gap:34px;margin-top:38px;flex-wrap:wrap}
.hero-stats .hs b{display:block;font-size:26px;font-weight:900;color:#fff}
.hero-stats .hs span{font-size:13px;color:#9fb3d6}
.hero-badges{display:flex;gap:10px;margin-top:26px;flex-wrap:wrap}
.hero-badges span{font-size:12.5px;font-weight:600;color:#cbe0ff;border:1px solid rgba(255,255,255,.18);
  background:rgba(255,255,255,.06);padding:6px 12px;border-radius:999px}

/* ---------- Section head ---------- */
.section-head{text-align:center;max-width:720px;margin:0 auto 56px}
.section-tag{display:inline-block;font-size:13px;font-weight:800;letter-spacing:1px;text-transform:uppercase;
  color:var(--brand);background:var(--bg-softer);border:1px solid var(--line-2);padding:6px 14px;border-radius:999px;margin-bottom:16px}
.section-head h2{font-size:clamp(28px,3.4vw,40px);font-weight:900;letter-spacing:-.4px;line-height:1.18}
.section-head p{color:var(--ink-2);font-size:17px;margin-top:14px}

/* ---------- Cards / Services ---------- */
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:26px}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:30px;
  box-shadow:var(--shadow-sm);transition:.3s;position:relative;overflow:hidden}
.card::before{content:"";position:absolute;inset:0 0 auto 0;height:4px;background:var(--grad);opacity:0;transition:.3s}
.card:hover{transform:translateY(-6px);box-shadow:var(--shadow);border-color:var(--line-2)}
.card:hover::before{opacity:1}
.card-art{width:120px;height:100px;margin-bottom:18px}
.card h3{font-size:20px;font-weight:800;margin-bottom:4px}
.card .en{font-size:12.5px;font-weight:700;color:var(--brand);letter-spacing:.4px;text-transform:uppercase}
.card p{color:var(--ink-2);font-size:15px;margin-top:12px}
.card ul{list-style:none;margin-top:14px;display:grid;gap:9px}
.card ul li{position:relative;padding-left:22px;font-size:14.5px;color:var(--ink-2)}
.card ul li::before{content:"";position:absolute;left:0;top:9px;width:9px;height:9px;border-radius:3px;
  background:var(--grad);transform:rotate(45deg)}

/* ---------- Stats band ---------- */
.stats-band{background:linear-gradient(120deg,#0a0f1e,#101a33);color:#fff;border-radius:26px;
  padding:54px 40px;display:grid;grid-template-columns:repeat(4,1fr);gap:24px;text-align:center;margin-top:8px}
.stats-band .st b{display:block;font-size:40px;font-weight:900;background:var(--grad);
  -webkit-background-clip:text;background-clip:text;color:transparent}
.stats-band .st span{color:#9fb3d6;font-size:14px;margin-top:6px;display:block}

/* ---------- CTA ---------- */
.cta{background:var(--grad);color:#fff;border-radius:26px;padding:56px 40px;text-align:center;
  box-shadow:var(--shadow-lg);position:relative;overflow:hidden}
.cta h2{font-size:clamp(26px,3vw,36px);font-weight:900}
.cta p{margin:14px auto 26px;max-width:560px;font-size:17px;color:rgba(255,255,255,.9)}

/* ---------- Chips ---------- */
.chips-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}
.chip-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:28px;text-align:center;
  box-shadow:var(--shadow-sm);transition:.3s}
.chip-card:hover{transform:translateY(-5px);box-shadow:var(--shadow)}
.logo-badge{width:64px;height:64px;margin:0 auto 14px;border-radius:16px;display:grid;place-items:center;
  background:var(--bg-softer);border:1px solid var(--line-2);font-weight:900;font-size:20px;color:var(--brand)}
.chip-card h4{font-size:17px;font-weight:800}
.chip-card p{color:var(--ink-2);font-size:14px;margin-top:6px}

/* ---------- Process steps ---------- */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:22px;counter-reset:s}
.step{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow-sm);position:relative}
.step .num{width:42px;height:42px;border-radius:12px;background:var(--grad);color:#fff;font-weight:900;
  display:grid;place-items:center;margin-bottom:14px;font-size:18px}
.step h4{font-size:17px;font-weight:800;margin-bottom:6px}
.step p{color:var(--ink-2);font-size:14.5px}

/* ---------- Spec table ---------- */
.spec-table{width:100%;border-collapse:collapse;background:#fff;border:1px solid var(--line);
  border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow-sm)}
.spec-table th,.spec-table td{padding:16px 18px;text-align:left;font-size:15px;border-bottom:1px solid var(--line)}
.spec-table thead th{background:var(--dark);color:#fff;font-weight:700}
.spec-table tbody tr:nth-child(even){background:var(--bg-soft)}
.spec-table tbody tr:hover{background:var(--bg-softer)}

/* ---------- Solutions detail ---------- */
.sol-detail{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.sol-box{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow-sm);transition:.3s}
.sol-box:hover{transform:translateY(-5px);box-shadow:var(--shadow)}
.sol-top{display:flex;align-items:center;gap:14px;margin-bottom:14px}
.sol-top .ic{width:54px;height:54px;border-radius:14px;background:var(--bg-softer);border:1px solid var(--line-2);
  display:grid;place-items:center;overflow:hidden}
.sol-top .ic img{width:100%;height:100%;object-fit:contain}
.sol-top h3{font-size:19px;font-weight:800}
.sol-top .en{font-size:12px;font-weight:700;color:var(--brand);text-transform:uppercase;letter-spacing:.4px}
.sol-body p{color:var(--ink-2);font-size:15px}
.sol-body ul{list-style:none;margin-top:12px;display:grid;gap:8px}
.sol-body ul li{position:relative;padding-left:20px;font-size:14.5px;color:var(--ink-2)}
.sol-body ul li::before{content:"";position:absolute;left:0;top:8px;width:8px;height:8px;border-radius:3px;background:var(--grad);transform:rotate(45deg)}

/* ---------- About ---------- */
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:50px;align-items:center}
.about-img img{width:100%;border-radius:24px;box-shadow:var(--shadow)}
.about-copy h2{font-size:clamp(26px,3vw,36px);font-weight:900;line-height:1.2;margin-bottom:18px}
.about-copy p{color:var(--ink-2);font-size:16.5px;margin-bottom:16px}
.about-points{display:grid;gap:14px;margin-top:22px}
.about-points .pt{display:flex;gap:12px;align-items:flex-start}
.about-points .pt .dot{width:26px;height:26px;border-radius:8px;background:var(--grad);color:#fff;display:grid;place-items:center;font-size:14px;flex:0 0 auto;margin-top:2px}
.about-points .pt b{font-weight:800}
.about-points .pt span{color:var(--ink-2);font-size:15px}
.facts{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:30px}
.fact{background:var(--bg-soft);border:1px solid var(--line);border-radius:14px;padding:18px}
.fact .k{font-size:13px;color:var(--ink-3);font-weight:600}
.fact .v{font-size:18px;font-weight:800;color:var(--brand);margin-top:4px}

/* ---------- Contact ---------- */
.contact-grid{display:grid;grid-template-columns:1fr 1.1fr;gap:40px;align-items:start}
.contact-info .info-item{display:flex;gap:16px;padding:18px 0;border-bottom:1px solid var(--line)}
.contact-info .info-item:last-child{border-bottom:0}
.contact-info .ic{width:48px;height:48px;border-radius:12px;background:var(--bg-softer);border:1px solid var(--line-2);
  display:grid;place-items:center;font-size:22px;flex:0 0 auto}
.contact-info h4{font-size:17px;font-weight:800}
.contact-info p{color:var(--ink-2);font-size:15px;margin-top:4px}
.contact-info a{color:var(--brand)}
.form-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:34px;box-shadow:var(--shadow-sm)}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.form-group{margin-bottom:16px}
.form-group label{display:block;font-size:14px;font-weight:700;margin-bottom:7px}
.form-group input,.form-group select,.form-group textarea{width:100%;padding:13px 14px;border:1px solid var(--line-2);
  border-radius:11px;font-size:15px;font-family:inherit;background:#fff;color:var(--ink);transition:.2s}
.form-group input:focus,.form-group select:focus,.form-group textarea:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 4px rgba(37,99,235,.12)}
.form-group textarea{min-height:120px;resize:vertical}
.form-note{font-size:13px;color:var(--ink-3);margin-top:6px}

/* ---------- Page hero (sub pages) ---------- */
.page-hero{position:relative;overflow:hidden;background:
   radial-gradient(900px 400px at 90% -20%,rgba(37,99,235,.30),transparent 60%),
   linear-gradient(160deg,#0a0f1e,#101a33);color:#fff;padding:84px 0 78px}
.page-hero .container{position:relative;z-index:2}
.breadcrumb{font-size:14px;color:#9fb3d6;margin-bottom:14px}
.breadcrumb a{color:#cbe0ff}
.breadcrumb a:hover{text-decoration:underline}
.page-hero h1{font-size:clamp(30px,4vw,46px);font-weight:900;letter-spacing:-.4px}
.page-hero p{color:#c5d2ea;font-size:18px;margin-top:12px;max-width:620px}

/* ---------- Footer ---------- */
.footer{background:var(--dark);color:#c5d2ea;padding:64px 0 30px}
.footer-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1.2fr;gap:36px}
.footer .logo{color:#fff}
.footer .logo small{color:#7e8db0}
.footer .desc{margin:16px 0;font-size:14.5px;max-width:340px;color:#9fb3d6}
.footer h4{color:#fff;font-size:16px;font-weight:800;margin-bottom:16px}
.footer ul{list-style:none;display:grid;gap:10px}
.footer ul a,.footer ul li{color:#9fb3d6;font-size:14.5px;transition:.2s}
.footer ul a:hover{color:#fff}
.socials{display:flex;gap:10px;margin-top:18px}
.socials a{width:40px;height:40px;border-radius:11px;background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.12);
  display:grid;place-items:center;font-size:18px;transition:.2s}
.socials a:hover{background:var(--brand);transform:translateY(-2px)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);margin-top:42px;padding-top:22px;font-size:13.5px;color:#7e8db0;text-align:center}

/* ---------- Reveal: disabled (content always visible, no JS dependency) ---------- */
.reveal{opacity:1;transform:none}

/* ---------- Lang: hide bilingual subtitles in EN ---------- */
html.lang-en .en,html.lang-en .en-title{display:none}

/* ---------- Responsive ---------- */
@media (max-width:980px){
  .hero .container{grid-template-columns:1fr;padding-top:70px;padding-bottom:80px}
  .hero-art{order:-1;max-width:460px;margin:0 auto}
  .cards,.sol-detail,.chips-grid,.steps,.facts{grid-template-columns:repeat(2,1fr)}
  .stats-band{grid-template-columns:repeat(2,1fr);gap:30px}
  .about-grid,.contact-grid{grid-template-columns:1fr;gap:34px}
  .nav-links{position:absolute;top:72px;left:0;right:0;flex-direction:column;gap:0;background:#fff;
    border-bottom:1px solid var(--line);padding:10px 24px;display:none;box-shadow:var(--shadow)}
  .nav-links.open{display:flex}
  .nav-links a{padding:14px 0;border-bottom:1px solid var(--line)}
  .menu-toggle{display:flex}
  .form-row{grid-template-columns:1fr}
}
@media (max-width:600px){
  section{padding:68px 0}
  .cards,.sol-detail,.chips-grid,.steps,.facts,.stats-band{grid-template-columns:1fr}
  .hero h1{font-size:32px}
  .cta,.stats-band{padding:40px 22px}
  .spec-table{display:block;overflow-x:auto;white-space:nowrap}
}