:root{
  --bg:#050505;
  --panel:#121212;
  --panel2:#1b1c20;
  --line:#2a2a2a;
  --text:#d7d9e0;
  --muted:#8a8d98;
  --accent:#3b82f6;
  --accent2:#2f6fd6;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  background:var(--bg);
  color:var(--text);
  font-family:"Segoe UI",-apple-system,"Microsoft YaHei",Roboto,Helvetica,Arial,sans-serif;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}

.nav{
  position:sticky;top:0;z-index:50;
  background:rgba(5,5,5,.85);
  border-bottom:1px solid var(--line);
  backdrop-filter:blur(8px);
}
.nav-inner{
  max-width:1080px;margin:0 auto;padding:14px 20px;
  display:flex;align-items:center;justify-content:space-between;
}
.brand{font-size:18px;font-weight:700;letter-spacing:.5px}
.brand-accent{color:var(--accent)}
.lang-btn{
  background:var(--panel2);color:var(--muted);border:1px solid var(--line);
  padding:6px 14px;border-radius:8px;cursor:pointer;font-size:13px;
  transition:color .15s,border-color .15s;
}
.lang-btn:hover{color:var(--text);border-color:var(--accent)}

.hero{border-bottom:1px solid var(--line)}
.hero-inner{max-width:1080px;margin:0 auto;padding:80px 20px 70px}
.hero-tag{
  display:inline-block;font-size:13px;color:var(--accent);
  border:1px solid var(--line);background:var(--panel);
  padding:5px 12px;border-radius:999px;margin-bottom:22px;
}
.hero h1{
  font-size:46px;font-weight:800;line-height:1.15;letter-spacing:.5px;
  margin-bottom:18px;
}
.hero-sub{max-width:680px;color:var(--muted);font-size:17px;margin-bottom:30px}
.hero-actions{display:flex;gap:14px;flex-wrap:wrap}
.hero-meta{margin-top:22px;color:var(--muted);font-size:13px}

.btn{
  display:inline-block;padding:12px 26px;border-radius:10px;font-size:15px;font-weight:600;
  cursor:pointer;transition:background .15s,transform .05s;
}
.btn:active{transform:translateY(1px)}
.btn-primary{background:var(--accent);color:#fff;border:1px solid var(--accent)}
.btn-primary:hover{background:var(--accent2)}
.btn-ghost{background:var(--panel);color:var(--text);border:1px solid var(--line)}
.btn-ghost:hover{border-color:var(--accent)}
.btn-lg{padding:15px 34px;font-size:16px}

.features{max-width:1080px;margin:0 auto;padding:70px 20px}
.feat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.feat{
  background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:24px;
}
.feat-ico{font-size:24px;color:var(--accent);margin-bottom:12px}
.feat h3{font-size:17px;margin-bottom:8px}
.feat p{color:var(--muted);font-size:14px}

.arch{border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:var(--panel)}
.arch{max-width:none}
.arch h2,.arch .arch-lead,.arch .arch-cols,.arch .arch-foot{max-width:1080px;margin-left:auto;margin-right:auto;padding-left:20px;padding-right:20px}
.arch{padding:70px 0}
.arch h2{font-size:32px;margin-bottom:12px}
.arch-lead{color:var(--muted);font-size:16px;margin-bottom:36px}
.arch-cols{display:grid;grid-template-columns:1fr 1fr;gap:20px}
.arch-col{background:var(--panel2);border:1px solid var(--line);border-radius:14px;padding:26px}
.arch-badge{display:inline-block;font-size:12px;font-weight:600;padding:5px 12px;border-radius:999px;margin-bottom:16px}
.arch-col.local .arch-badge{color:var(--accent);background:rgba(59,130,246,.1);border:1px solid rgba(59,130,246,.3)}
.arch-col.cloud .arch-badge{color:#7fe0a8;background:rgba(127,224,168,.1);border:1px solid rgba(127,224,168,.3)}
.arch-col h3{font-size:19px;margin-bottom:16px}
.arch-flow{list-style:none;counter-reset:step}
.arch-flow li{counter-increment:step;position:relative;padding-left:34px;margin-bottom:12px;color:var(--text);font-size:14px}
.arch-flow li::before{
  content:counter(step);position:absolute;left:0;top:1px;
  width:22px;height:22px;border-radius:50%;background:var(--line);color:var(--text);
  font-size:12px;font-weight:700;display:flex;align-items:center;justify-content:center;
}
.arch-note{margin-top:14px;color:var(--muted);font-size:13px;border-top:1px dashed var(--line);padding-top:12px}
.arch-foot{margin-top:34px;color:var(--muted);font-size:14px;line-height:1.7}

.download{max-width:1080px;margin:0 auto;padding:70px 20px;text-align:center}
.download h2{font-size:32px;margin-bottom:12px}
.dl-sub{color:var(--muted);font-size:16px;margin-bottom:28px}
.dl-req{margin-top:18px;color:var(--muted);font-size:13px}

.foot{border-top:1px solid var(--line);padding:30px 20px;text-align:center;color:var(--muted);font-size:13px}

@media(max-width:820px){
  .feat-grid{grid-template-columns:1fr 1fr}
  .arch-cols{grid-template-columns:1fr}
  .hero h1{font-size:34px}
}
@media(max-width:540px){
  .feat-grid{grid-template-columns:1fr}
}