/* ============================================================
   KOTI 全站统一设计系统 (koti.css)
   融合 index 的 hero-grid 体系与子页的 pb-hero/grid3/sclist 体系
   全站（中英文，首页+子页）共用，视觉彻底统一
   ============================================================ */
:root{
  --bg:#0B0F14; --bg2:#121821; --bg3:#1A2230;
  --line:rgba(255,255,255,.10); --line2:rgba(255,255,255,.18);
  --txt:#E8EDF3; --txt2:#9AA7B8; --txt3:#6B7787;
  --brand:#FF8C1A; --brand2:#F5A623; --brand-dim:rgba(255,140,26,.12);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{background:var(--bg);color:var(--txt);font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;line-height:1.7;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
img{max-width:100%}
.wrap{max-width:1200px;margin:0 auto;padding:0 24px}
.narrow{max-width:820px;margin:0 auto;padding:0 24px}

/* ---------- nav ---------- */
.nav{position:sticky;top:0;z-index:100;background:rgba(11,15,20,.88);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.nav-in{display:flex;align-items:center;justify-content:space-between;height:68px}
.logo{display:flex;align-items:baseline;gap:10px;font-size:22px;font-weight:700;letter-spacing:.5px}
.logo em{font-style:normal;color:var(--brand)}
.logo span{font-size:12px;color:var(--txt3);font-weight:400;letter-spacing:2px}
.menu{display:flex;gap:30px;font-size:15px;color:var(--txt2)}
.menu a:hover{color:var(--brand)}
.nav-cta{display:flex;align-items:center;gap:16px}
.tel{font-size:15px;color:var(--txt2);font-variant-numeric:tabular-nums}
.tel b{color:var(--brand);font-weight:600}
.btn{background:var(--brand);color:#0B0F14;padding:10px 22px;border-radius:6px;font-size:15px;font-weight:600;display:inline-block;transition:.2s;border:none;cursor:pointer}
.btn:hover{background:var(--brand2);transform:translateY(-1px)}
.btn-o{border:1px solid var(--brand);color:var(--brand);background:transparent}
.btn-o:hover{background:var(--brand-dim)}
.burger{display:none;background:none;border:1px solid var(--line2);color:var(--txt);font-size:18px;padding:6px 12px;border-radius:6px;cursor:pointer}
.lang-switch{border:1px solid var(--line2);padding:4px 12px;border-radius:100px;font-size:13px;color:var(--txt3);margin-left:8px;transition:.2s}
.lang-switch:hover{border-color:var(--brand);color:var(--brand)}

/* ---------- breadcrumb ---------- */
.crumb{padding:22px 0 0;font-size:13.5px;color:var(--txt3)}
.crumb a:hover{color:var(--brand)}
.crumb b{color:var(--txt2);font-weight:400}

/* ---------- HERO（首页大图墙型） ---------- */
.hero{padding:80px 0 34px;position:relative;overflow:hidden;
  background:radial-gradient(820px 400px at 82% 0%,rgba(255,140,26,.15),transparent 60%),
             linear-gradient(180deg,#0B0F14 0%,#0B0F14 72%,#0E141B 100%)}
.hero::before{content:"";position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.045) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px);background-size:46px 46px;
  -webkit-mask-image:radial-gradient(ellipse 85% 75% at 50% 25%,#000 35%,transparent 100%);mask-image:radial-gradient(ellipse 85% 75% at 50% 25%,#000 35%,transparent 100%);pointer-events:none}
.hero-grid{display:grid;grid-template-columns:1.04fr .96fr;gap:50px;align-items:center;position:relative;z-index:1}
.hero-text{max-width:none}
.hero-visual{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.hv{position:relative;border-radius:14px;overflow:hidden;border:1px solid var(--line);aspect-ratio:1/1;display:block;transition:.3s;background:var(--bg3)}
.hv img{width:100%;height:100%;object-fit:cover;opacity:.88;transition:.35s}
.hv:hover{border-color:var(--brand);transform:translateY(-3px)}
.hv:hover img{opacity:1;transform:scale(1.06)}
.hv b{position:absolute;left:12px;bottom:11px;font-size:13px;font-weight:600;color:#fff;text-shadow:0 1px 6px rgba(0,0,0,.85);z-index:2}
.hv::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,transparent 52%,rgba(11,15,20,.72) 100%)}
.hv .corner{position:absolute;top:10px;right:11px;font-size:10.5px;letter-spacing:1px;color:var(--brand);border:1px solid rgba(255,140,26,.5);padding:2px 7px;border-radius:100px;z-index:2;background:rgba(11,15,20,.5)}
.tag{display:inline-block;border:1px solid var(--brand);color:var(--brand);font-size:13px;padding:5px 14px;border-radius:100px;margin-bottom:22px;letter-spacing:1px}
h1{font-size:48px;line-height:1.28;font-weight:700;letter-spacing:-.5px}
h1 em{font-style:normal;color:var(--brand)}
.sub{font-size:18px;color:var(--txt2);margin-top:22px;max-width:680px}
.hero-btns{display:flex;gap:14px;margin-top:34px;flex-wrap:wrap}
.brand-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-top:46px;padding-top:30px;border-top:1px dashed var(--line2)}
.brand-strip .it{padding:10px 14px;background:rgba(255,255,255,.03);border:1px solid var(--line);border-radius:8px;display:flex;align-items:center;gap:12px;min-height:54px}
.brand-strip .sq{width:10px;height:10px;border-radius:2px;background:var(--brand);flex-shrink:0}
.brand-strip b{font-size:14.5px;letter-spacing:.5px}
.brand-strip span{font-size:12px;color:var(--txt3)}

/* ---------- PAGE-HERO（子页标题型首屏，与 hero 同设计语言） ---------- */
.pb-hero{padding:46px 0 34px;position:relative;overflow:hidden;
  background:radial-gradient(820px 380px at 80% 0%,rgba(255,140,26,.14),transparent 60%),linear-gradient(180deg,#0B0F14,#0E141B)}
.pb-hero .kicker{display:inline-block;border:1px solid var(--brand);color:var(--brand);font-size:12.5px;padding:5px 14px;border-radius:100px;margin-bottom:18px;letter-spacing:1px}
.pb-hero h1{font-size:42px;line-height:1.25;font-weight:700;letter-spacing:-.5px}
.pb-hero h1 em{font-style:normal;color:var(--brand)}
.pb-hero .lead{font-size:17px;color:var(--txt2);margin-top:18px;max-width:780px}
.pb-hero .links{margin-top:22px;display:flex;gap:10px;flex-wrap:wrap}
.pb-hero .links a{font-size:13.5px;color:var(--txt2);border:1px solid var(--line2);padding:7px 14px;border-radius:6px}
.pb-hero .links a:hover{border-color:var(--brand);color:var(--brand)}

/* ---------- stats ---------- */
.stats{border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:var(--bg2)}
.stats-in{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;padding:30px 0;text-align:center}
.stat b{display:block;font-size:33px;color:var(--brand);font-weight:700;font-variant-numeric:tabular-nums;line-height:1.2;text-shadow:0 0 18px rgba(255,140,26,.35)}
.stat span{font-size:13.5px;color:var(--txt3)}

/* ---------- section 基础 ---------- */
section{padding:84px 0}
.sec-tag{color:var(--brand);font-size:13px;letter-spacing:3px;margin-bottom:12px}
h2{font-size:34px;font-weight:700;line-height:1.35;letter-spacing:-.3px}
.sec-sub{color:var(--txt2);font-size:16.5px;margin-top:14px;max-width:720px}
.head{margin-bottom:46px}

/* ---------- 通用卡片 grid3 / card ---------- */
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.card{position:relative;background:var(--bg2);border:1px solid var(--line);border-radius:12px;overflow:hidden;transition:.25s;display:flex;flex-direction:column}
.card:hover{border-color:var(--brand);transform:translateY(-4px)}
.card .ph{aspect-ratio:4/3;background:var(--bg3);position:relative;overflow:hidden;display:flex;align-items:center;justify-content:center}
.card .ph img{width:100%;height:100%;object-fit:cover;opacity:.92}
.card .ph::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,transparent 55%,rgba(11,15,20,.78) 100%)}
.card .meta{padding:18px 20px 22px;flex:1;display:flex;flex-direction:column}
.card .tag2{font-size:11px;color:var(--brand);letter-spacing:2px;margin-bottom:6px}
.card h3{font-size:18px;font-weight:600;margin-bottom:8px}
.card h4{font-size:16px;font-weight:600;margin-bottom:8px;color:var(--txt)}
.card p{font-size:13.5px;color:var(--txt2);flex:1}
.card .more{font-size:13px;color:var(--brand);margin-top:14px;display:inline-block}

/* ---------- 首页品牌卡 grid4 / brand-card ---------- */
.grid4{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.brand-card{background:var(--bg2);border:1px solid var(--line);border-radius:12px;overflow:hidden;transition:.25s;display:flex;flex-direction:column}
.brand-card:hover{border-color:var(--brand);transform:translateY(-4px)}
.brand-card .ph{aspect-ratio:4/3;background:var(--bg3);position:relative;overflow:hidden;display:flex;align-items:center;justify-content:center}
.brand-card .ph img{width:100%;height:100%;object-fit:cover;opacity:.9}
.brand-card .ph::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,transparent 50%,rgba(11,15,20,.7) 100%)}
.brand-card .meta{padding:18px 20px 22px;flex:1;display:flex;flex-direction:column}
.brand-card .tag2{font-size:11px;color:var(--brand);letter-spacing:2px;margin-bottom:6px}
.brand-card h3{font-size:19px;font-weight:600;margin-bottom:8px}
.brand-card p{font-size:13.5px;color:var(--txt2);flex:1}
.brand-card .more{font-size:13px;color:var(--brand);margin-top:14px;display:inline-block}

/* ---------- 场景卡 scenes / grid3 / scene ---------- */
.scenes{background:var(--bg2)}
.scene{background:var(--bg);border:1px solid var(--line);border-radius:12px;overflow:hidden;transition:.25s}
.scene:hover{border-color:var(--brand);transform:translateY(-3px)}
.scene .ph{aspect-ratio:16/9;background:var(--bg3);overflow:hidden}
.scene .ph img{width:100%;height:100%;object-fit:cover}
.scene .meta{padding:22px}
.scene h3{font-size:18px;font-weight:600;margin-bottom:6px}
.scene .sub2{font-size:13px;color:var(--brand);margin-bottom:12px}
.scene ul{list-style:none;margin-top:12px}
.scene li{font-size:14px;color:var(--txt2);padding:6px 0;border-top:1px dashed var(--line)}
.scene li:first-child{border-top:none}

/* ---------- 场景/服务网络列表 sclist / sci ---------- */
.sclist{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}
.sci{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:22px 24px;transition:.25s}
.sci:hover{border-color:var(--brand)}
.sci h4{font-size:16px;font-weight:600;margin-bottom:8px;color:var(--txt)}
.sci p{font-size:14px;color:var(--txt2)}
.sci .tag{font-size:11.5px;color:var(--brand);letter-spacing:1px;margin-bottom:10px}

/* ---------- 为什么选我们 vgrid / vitem ---------- */
.value{background:var(--bg3);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.vgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.vitem{border-left:2px solid var(--line2);padding:4px 0 4px 22px;transition:.25s}
.vitem:hover{border-left-color:var(--brand)}
.vitem h4{font-size:16.5px;font-weight:600;margin-bottom:7px}
.vitem p{font-size:14px;color:var(--txt2)}

/* ---------- about / prose / factbox ---------- */
.about{display:grid;grid-template-columns:1.4fr 1fr;gap:36px;align-items:start}
.prose p{font-size:15.5px;color:var(--txt2);margin-bottom:14px}
.prose p b{color:var(--txt)}
.factbox{background:var(--bg2);border:1px solid var(--line);border-radius:14px;padding:24px 26px}
.factbox h4{font-size:14px;color:var(--brand);letter-spacing:1px;margin-bottom:14px}
.factbox ul{list-style:none}
.factbox li{font-size:14px;color:var(--txt2);padding:9px 0;border-top:1px dashed var(--line);display:flex;justify-content:space-between;gap:16px}
.factbox li:first-child{border-top:none}
.factbox li span{color:var(--txt3);font-size:12.5px;text-align:right;flex-shrink:0}

/* ---------- 落地流程 steps / step ---------- */
.steps{counter-reset:s;display:grid;grid-template-columns:repeat(5,1fr);gap:14px;margin-top:8px}
.step{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:20px 16px;transition:.25s}
.step:hover{border-color:var(--brand)}
.step .n{width:30px;height:30px;border-radius:50%;background:var(--brand);color:#0B0F14;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:14px;margin-bottom:12px}
.step h4{font-size:15px;font-weight:600;margin-bottom:6px}
.step p{font-size:13px;color:var(--txt2)}

/* ---------- 数据表 dtable ---------- */
.dtable{width:100%;border-collapse:collapse;font-size:13.5px;margin-top:8px;overflow:hidden;border-radius:10px}
.dtable th,.dtable td{border:1px solid var(--line);padding:11px 13px;text-align:left;vertical-align:top}
.dtable th{background:var(--bg3);color:var(--brand);font-weight:600;font-size:12.5px;letter-spacing:.5px}
.dtable td b{color:var(--txt)}
.dtable tr:nth-child(even) td{background:rgba(255,255,255,.02)}
.dtable .hl{color:var(--brand);font-weight:600}

/* ---------- 样板点 case ---------- */
.case{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:22px 24px;transition:.25s;position:relative;overflow:hidden}
.case:hover{border-color:var(--brand)}
.case .badge{display:inline-block;font-size:11px;letter-spacing:1px;color:var(--brand);border:1px solid rgba(255,140,26,.5);padding:3px 10px;border-radius:100px;margin-bottom:10px}
.case h4{font-size:16.5px;font-weight:600;margin-bottom:8px}
.case p{font-size:14px;color:var(--txt2)}
.case .coming{position:absolute;top:14px;right:14px;font-size:11px;color:var(--txt3);background:var(--bg3);border:1px solid var(--line);padding:3px 10px;border-radius:100px}
.case .live{position:absolute;top:14px;right:14px;font-size:11px;color:#3fd07d;background:rgba(63,208,125,.12);border:1px solid rgba(63,208,125,.4);padding:3px 10px;border-radius:100px}

/* ---------- 合规/提示 note / source ---------- */
.note{background:var(--brand-dim);border:1px solid rgba(255,140,26,.4);border-radius:12px;padding:20px 24px;font-size:13.5px;color:var(--txt2)}
.note b{color:var(--brand)}
.source{font-size:12.5px;color:var(--txt3);padding:18px 0 0;border-top:1px dashed var(--line);margin-top:8px}
.source a{color:var(--txt3);text-decoration:underline}

/* ---------- 信息卡 info / inf（联系页） ---------- */
.info{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.inf{background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:20px 22px}
.inf h5{font-size:14px;color:var(--brand);margin-bottom:8px;letter-spacing:1px}
.inf p{font-size:14.5px;color:var(--txt);line-height:1.7}
.inf b{color:var(--brand)}

/* ---------- CTA ---------- */
.cta{background:var(--bg2);border:1px solid var(--line);border-radius:16px;padding:42px;text-align:center}
.cta h2{font-size:28px}
.cta p{color:var(--txt2);margin-top:12px}

/* ---------- 表单 form ---------- */
.form-wrap{background:var(--bg2);border:1px solid var(--line);border-radius:16px;padding:42px}
.form-wrap h2{font-size:28px}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:0 18px}
.field{margin-bottom:16px}
.field label{display:block;font-size:14px;color:var(--txt2);margin-bottom:7px}
.field input,.field select,.field textarea{width:100%;background:var(--bg);border:1px solid var(--line2);border-radius:8px;padding:12px 14px;color:var(--txt);font-size:15px;font-family:inherit;outline:none;transition:.2s}
.field input:focus,.field select:focus,.field textarea:focus{border-color:var(--brand)}
.field select{appearance:none;cursor:pointer}
.field textarea{resize:vertical;min-height:84px}
.tip{font-size:13px;color:var(--txt3);margin-top:14px}
.form-ok{display:none;background:var(--brand-dim);border:1px solid var(--brand);border-radius:8px;padding:18px;margin-top:18px}
.form-ok.show{display:block}

/* ---------- footer ---------- */
footer{background:var(--bg2);border-top:1px solid var(--line);padding:50px 0 26px;font-size:14px;color:var(--txt3)}
.f-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:36px;margin-bottom:36px}
.f-grid h5{color:var(--txt);font-size:15px;font-weight:600;margin-bottom:14px}
.f-grid li{list-style:none;margin-bottom:9px}
.f-grid a:hover{color:var(--brand)}
.f-bot{border-top:1px solid var(--line);padding-top:22px;display:flex;flex-direction:row;align-items:center;justify-content:center;text-align:center;gap:10px;flex-wrap:wrap;font-size:12.5px}
.f-bot a{color:var(--brand);text-decoration:underline}
.f-band{display:flex;flex-direction:column;align-items:center;text-align:center;gap:28px;border-top:1px solid var(--line);padding-top:28px;margin-top:8px}
.f-band h5{color:var(--txt);font-size:15px;font-weight:600;margin-bottom:14px;letter-spacing:.5px}
.f-band .fcol{width:100%;max-width:720px}
.soc{display:flex;flex-wrap:wrap;gap:10px 18px;justify-content:center;margin-top:2px}
.soc-it{display:inline-flex;align-items:center;gap:6px;color:var(--txt2);font-size:13.5px;white-space:nowrap}
.soc-add{margin-top:16px;font-size:13.5px;color:var(--txt3)}
.soc-add a{color:var(--brand)}
.f-qr{display:flex;justify-content:center;gap:36px;flex-wrap:wrap;margin-top:4px}
.f-qr .qr{display:flex;flex-direction:column;align-items:center;gap:8px}
.f-qr .qr img{width:96px;height:96px;border:1px solid var(--line2);border-radius:8px;background:#fff;display:block}
.f-qr .qr span{font-size:12.5px;color:var(--txt3)}

/* ---------- float ---------- */
.float{position:fixed;right:20px;bottom:20px;z-index:99;display:flex;flex-direction:column;gap:10px}
.float a{width:54px;height:54px;border-radius:50%;background:var(--brand);color:#0B0F14;display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:600;box-shadow:0 6px 20px rgba(0,0,0,.4)}
.float a.sec{background:var(--bg3);color:var(--brand);border:1px solid var(--brand)}

/* ---------- reveal 动画 ---------- */
.reveal{opacity:0;transform:translateY(22px);transition:.6s ease}
.reveal.in{opacity:1;transform:none}

/* ---------- 响应式 ---------- */
@media(max-width:900px){
  .menu,.tel{display:none}
  .burger{display:block}
  h1,.pb-hero h1{font-size:30px}
  h2{font-size:24px}
  .hero{padding:50px 0 30px}
  .hero-grid{grid-template-columns:1fr;gap:30px}
  .hero-visual{max-width:440px;margin:0 auto;width:100%}
  .grid4,.grid3,.vgrid,.sclist,.about{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr 1fr}
  .info,.form-grid{grid-template-columns:1fr}
  .brand-strip{grid-template-columns:repeat(2,1fr)}
  .f-grid{grid-template-columns:1fr 1fr}
  .f-band{gap:22px;padding-top:24px}
  section{padding:54px 0}
  .stats-in{gap:24px 12px}
}
@media(max-width:560px){
  .grid4,.grid3,.vgrid,.sclist{grid-template-columns:1fr}
  .brand-strip{grid-template-columns:1fr}
  .stats-in{grid-template-columns:repeat(2,1fr)}
  .f-grid{grid-template-columns:1fr}
  .stat b{font-size:24px}
  h1{font-size:28px}
  .pb-hero h1{font-size:26px}
}

/* 导航下拉（产品方案） */
.nav-item{position:relative}
.nav-item .caret{font-size:10px;opacity:.7;margin-left:1px;display:inline-block;transition:transform .2s}.nav-item.open .caret{transform:rotate(180deg)}
.dropdown{position:absolute;top:100%;left:0;min-width:212px;background:rgba(18,24,33,.98);border:1px solid var(--line2);border-radius:10px;padding:7px;display:none;flex-direction:column;gap:2px;box-shadow:0 12px 32px rgba(0,0,0,.45);z-index:200;margin-top:8px}
.nav-item.open .dropdown{display:flex}
.dropdown a{padding:9px 12px;border-radius:7px;font-size:14px;color:var(--txt2);white-space:nowrap;transition:.15s}
.dropdown a:hover{background:var(--brand-dim);color:var(--brand)}
@media(max-width:900px){
  .nav-item.has-drop{position:static}
  .dropdown{position:static;display:none;min-width:0;background:transparent;border:none;box-shadow:none;padding:2px 0 6px 14px;margin-top:0}
  .nav-item.open .dropdown{display:flex}
  .dropdown a{font-size:14px}
}