:root{--p:#3b82f6;--pd:#1d4ed8;--a:#f59e0b;--tint:#eff6ff;--ink:#111827;--muted:#6b7280;--line:#e5e7eb}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;color:var(--ink);background:#fff;line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{max-width:1120px;margin:0 auto;padding:0 24px}
/* nav */
.nav{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.86);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:17px}
.brand .dot{width:34px;height:34px;border-radius:10px;background:linear-gradient(135deg,var(--p),var(--a));display:flex;align-items:center;justify-content:center;color:#fff;font-size:16px;font-weight:800}
.nav-links{display:flex;gap:26px;font-size:14px;color:var(--muted)}
.nav-links a:hover{color:var(--p)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border-radius:12px;font-weight:600;cursor:pointer;border:none;transition:.2s}
.btn-p{background:linear-gradient(135deg,var(--p),var(--pd));color:#fff;padding:12px 26px;font-size:15px;box-shadow:0 8px 20px -8px var(--p)}
.btn-p:hover{transform:translateY(-2px);box-shadow:0 12px 26px -8px var(--p)}
.btn-o{background:#fff;color:var(--p);padding:11px 24px;font-size:15px;border:1.5px solid var(--p)}
.btn-o:hover{background:var(--tint)}
.btn-sm{padding:8px 18px;font-size:13.5px;border-radius:10px}
/* hero */
.hero{position:relative;overflow:hidden;background:linear-gradient(180deg,var(--tint),#fff 82%)}
.hero::before{content:"";position:absolute;width:520px;height:520px;border-radius:50%;background:radial-gradient(circle,var(--p) 0%,transparent 70%);opacity:.13;top:-220px;right:-140px}
.hero::after{content:"";position:absolute;width:380px;height:380px;border-radius:50%;background:radial-gradient(circle,var(--a) 0%,transparent 70%);opacity:.12;bottom:-180px;left:-120px}
.hero-inner{position:relative;display:grid;grid-template-columns:1.05fr .95fr;gap:48px;align-items:center;padding:72px 0 84px}
.badge{display:inline-flex;align-items:center;gap:6px;background:#fff;border:1px solid var(--line);color:var(--pd);font-size:12.5px;font-weight:600;padding:6px 14px;border-radius:999px;box-shadow:0 2px 8px rgba(0,0,0,.04)}
.hero h1{font-size:clamp(30px,4.4vw,46px);line-height:1.22;margin:18px 0 14px;letter-spacing:.5px}
.hero h1 em{font-style:normal;background:linear-gradient(120deg,var(--p),var(--a));-webkit-background-clip:text;background-clip:text;color:transparent}
.hero .sub{font-size:16.5px;color:var(--muted);max-width:520px;margin-bottom:30px}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap}
.hero-media{position:relative}
.hero-media img{width:100%;aspect-ratio:1/1;object-fit:cover;border-radius:24px;box-shadow:0 30px 60px -22px rgba(0,0,0,.28)}
.hero-media .float{position:absolute;background:#fff;border-radius:14px;box-shadow:0 14px 30px -12px rgba(0,0,0,.18);padding:10px 16px;font-size:13px;font-weight:600;display:flex;align-items:center;gap:8px}
.hero-media .f1{top:-16px;left:-14px;color:var(--pd)}
.hero-media .f2{bottom:-16px;right:-10px;color:var(--pd)}
/* platform strip */
.strip{border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:#fafbfc}
.strip-inner{display:flex;justify-content:space-around;flex-wrap:wrap;padding:18px 0;gap:10px}
.chip{display:flex;align-items:center;gap:8px;font-size:13.5px;color:var(--muted);font-weight:500}
.chip b{color:var(--ink)}
/* sections */
section{padding:76px 0}
.sec-head{text-align:center;max-width:640px;margin:0 auto 46px}
.sec-head .kicker{color:var(--p);font-weight:700;font-size:13px;letter-spacing:2px}
.sec-head h2{font-size:clamp(24px,3vw,32px);margin:10px 0 12px}
.sec-head p{color:var(--muted);font-size:15px}
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.card{background:#fff;border:1px solid var(--line);border-radius:18px;padding:26px 24px;transition:.25s}
.card:hover{transform:translateY(-4px);box-shadow:0 18px 40px -18px rgba(0,0,0,.14);border-color:var(--p)}
.card .ico{width:48px;height:48px;border-radius:13px;background:var(--tint);display:flex;align-items:center;justify-content:center;font-size:24px;margin-bottom:16px}
.card h3{font-size:16.5px;margin-bottom:8px}
.card p{font-size:13.8px;color:var(--muted)}
/* flow */
.flow{background:linear-gradient(180deg,#fff,var(--tint))}
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.step{position:relative;background:#fff;border:1px solid var(--line);border-radius:18px;padding:26px 22px}
.step .num{position:absolute;top:-16px;left:22px;width:32px;height:32px;border-radius:50%;background:linear-gradient(135deg,var(--p),var(--pd));color:#fff;font-weight:800;display:flex;align-items:center;justify-content:center;font-size:14px;box-shadow:0 6px 14px -6px var(--p)}
.step h3{font-size:15.5px;margin:8px 0 6px}
.step p{font-size:13px;color:var(--muted)}
/* cta */
.cta-band{background:linear-gradient(120deg,var(--pd),var(--p));border-radius:24px;padding:52px 48px;color:#fff;display:flex;align-items:center;justify-content:space-between;gap:24px;flex-wrap:wrap;position:relative;overflow:hidden}
.cta-band::after{content:"";position:absolute;width:300px;height:300px;border-radius:50%;background:rgba(255,255,255,.08);right:-80px;top:-120px}
.cta-band h2{font-size:clamp(20px,2.6vw,27px);position:relative}
.cta-band p{opacity:.85;font-size:14px;margin-top:6px;position:relative}
.cta-band .btn{background:#fff;color:var(--pd);position:relative}
/* footer */
footer{border-top:1px solid var(--line);padding:30px 0 40px;font-size:13px;color:var(--muted)}
.foot-inner{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;align-items:center}
footer a{color:var(--p)}
/* toast */
#toast{position:fixed;left:50%;bottom:36px;transform:translateX(-50%) translateY(20px);background:rgba(17,24,39,.92);color:#fff;padding:12px 22px;border-radius:12px;font-size:14px;opacity:0;pointer-events:none;transition:.3s;z-index:99}
#toast.show{opacity:1;transform:translateX(-50%) translateY(0)}
/* responsive */
@media(max-width:900px){
  .hero-inner{grid-template-columns:1fr;padding:48px 0 60px}
  .grid-3{grid-template-columns:1fr 1fr}
  .steps{grid-template-columns:1fr 1fr}
  .nav-links{display:none}
}
@media(max-width:560px){
  .grid-3{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr}
  .cta-band{padding:36px 26px}
}