:root{
  --bg:#0f172a; --bg2:#111c34; --fg:#0f172a; --muted:#64748b;
  --brand:#2563eb; --brand2:#1d4ed8; --accent:#10b981; --danger:#ef4444;
  --card:#ffffff; --line:#e2e8f0; --soft:#f8fafc;
}
*{box-sizing:border-box}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--fg);background:var(--soft);line-height:1.6}
a{color:var(--brand);text-decoration:none}
.btn{display:inline-block;padding:10px 18px;border-radius:10px;border:1px solid transparent;font-weight:600;cursor:pointer;font-size:14px}
.btn-primary{background:var(--brand);color:#fff}
.btn-primary:hover{background:var(--brand2)}
.btn-ghost{background:transparent;border-color:var(--line);color:var(--fg)}
.btn-ghost:hover{border-color:var(--brand);color:var(--brand)}
.btn-sm{padding:6px 12px;font-size:13px}
.btn-danger{background:#fff;border-color:var(--danger);color:var(--danger)}
.btn-danger:hover{background:var(--danger);color:#fff}
.btn.block{display:block;width:100%;text-align:center;margin-top:12px}

/* 导航 */
.nav{display:flex;align-items:center;justify-content:space-between;padding:16px 28px;background:#fff;border-bottom:1px solid var(--line)}
.brand{font-weight:800;font-size:18px;color:var(--brand)}
.badge{font-size:11px;background:var(--accent);color:#fff;padding:2px 8px;border-radius:999px;margin-left:6px;vertical-align:middle}
.nav nav{display:flex;align-items:center;gap:14px}
.nav .who{color:var(--muted);font-size:14px}

/* 落地页 */
.landing{background:linear-gradient(160deg,#0f172a,#1e3a8a)}
.landing .nav{background:transparent;border:0}
.landing .nav a{color:#cbd5e1}
.landing .brand{color:#fff}
.hero{max-width:820px;margin:60px auto 40px;text-align:center;color:#fff;padding:0 20px}
.hero h1{font-size:40px;line-height:1.2;margin-bottom:16px}
.hero p{font-size:18px;color:#cbd5e1;margin-bottom:28px}
.features{max-width:1000px;margin:0 auto;display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:18px;padding:20px}
.card{background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.12);border-radius:16px;padding:22px;color:#e2e8f0}
.card .ico{font-size:30px}
.card h3{margin:10px 0 6px;color:#fff}
.get{max-width:720px;margin:40px auto;background:#fff;border-radius:18px;padding:30px;box-shadow:0 10px 30px rgba(0,0,0,.08)}
.get h2{margin-top:0}
.steps{padding-left:20px}
.steps li{margin:8px 0}
.hint{color:var(--muted);font-size:14px}
.foot{text-align:center;color:#94a3b8;padding:30px}

/* 认证页 */
.auth{display:flex;align-items:center;justify-content:center;min-height:100vh;background:linear-gradient(160deg,#0f172a,#1e3a8a)}
.auth-box{background:#fff;border-radius:18px;padding:34px;width:360px;box-shadow:0 20px 60px rgba(0,0,0,.3)}
.auth-box h2{margin:6px 0 4px}
.auth-box .brand{font-size:22px;margin-bottom:14px}
.center{text-align:center}
.muted{color:var(--muted);font-size:14px}
.auth-box label{display:block;font-size:13px;margin:12px 0 4px;color:var(--muted)}
.auth-box input{width:100%;padding:11px;border:1px solid var(--line);border-radius:10px;font-size:14px}
.alert{padding:10px 12px;border-radius:10px;font-size:14px;margin:10px 0}
.alert.err{background:#fef2f2;color:#b91c1c}
.alert.ok{background:#ecfdf5;color:#047857}
.back{margin-top:14px;font-size:13px;text-align:center}

/* 后台 */
.admin .nav{background:#fff}
.wrap{max-width:1000px;margin:24px auto;padding:0 20px}
.stat-row{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-bottom:20px}
.stat{background:#fff;border:1px solid var(--line);border-radius:14px;padding:18px;text-align:center}
.stat .num{font-size:24px;font-weight:800;color:var(--brand)}
.stat .lbl{color:var(--muted);font-size:13px}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:20px}
.panel{background:#fff;border:1px solid var(--line);border-radius:14px;padding:20px;margin-bottom:20px}
.panel h3{margin-top:0}
.form-inline{display:flex;flex-wrap:wrap;gap:8px}
.form-inline input{flex:1;min-width:140px;padding:10px;border:1px solid var(--line);border-radius:10px}
.tbl{width:100%;border-collapse:collapse}
.tbl th,.tbl td{padding:10px;border-bottom:1px solid var(--line);text-align:left;font-size:14px}
.tbl th{color:var(--muted);font-weight:600}
.tbl .empty{color:var(--muted);text-align:center;padding:24px}

/* 弹窗 */
.modal{position:fixed;inset:0;background:rgba(15,23,42,.6);display:flex;align-items:center;justify-content:center;z-index:50}
.modal.hidden{display:none}
.modal-box{background:#fff;border-radius:16px;padding:24px;width:420px;max-width:92vw;position:relative}
.modal-box .close{position:absolute;top:10px;right:14px;border:0;background:none;font-size:26px;cursor:pointer;color:var(--muted)}
.qr{background:#fff;border:1px solid var(--line);border-radius:12px;padding:12px;display:flex;justify-content:center;margin:10px 0}
.qr svg{width:220px;height:220px}
.qr-fallback{color:var(--muted);font-size:13px;padding:30px 10px;text-align:center}
.conf{background:#0f172a;color:#e2e8f0;padding:14px;border-radius:10px;font-size:12px;overflow:auto;white-space:pre-wrap;max-height:200px}

@media(max-width:720px){
  .grid2{grid-template-columns:1fr}
  .stat-row{grid-template-columns:1fr}
}