:root{
  --bg:#f8fafc; --card:#ffffff; --fg:#0f172a; --muted:#64748b;
  --primary:#0284c7; --primary-2:#38bdf8; --border:#e2e8f0;
  --grad:linear-gradient(135deg,#0284c7,#38bdf8);
  --shadow:0 10px 30px -10px rgba(2,132,199,.35);
}
*{box-sizing:border-box}
html,body{margin:0;padding:0;background:var(--bg);color:var(--fg);font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.55}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;display:block}
.container{max-width:1100px;margin:0 auto;padding:0 16px}

/* Header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.85);backdrop-filter:blur(8px);border-bottom:1px solid var(--border)}
.nav-bar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:12px 16px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;color:var(--fg)}
.brand-mark{width:30px;height:30px;border-radius:8px;background:var(--grad)}
.nav-links{display:flex;flex-wrap:wrap;gap:4px;font-size:14px}
.nav-links a{padding:6px 12px;border-radius:8px;color:#475569}
.nav-links a:hover{background:#e0f2fe;color:var(--primary);text-decoration:none}
.nav-links a.active{background:#e0f2fe;color:var(--primary);font-weight:600}

/* Hero */
.hero{position:relative;color:#fff;padding:48px 0;overflow:hidden;border-bottom:1px solid var(--border)}
.hero::before{content:"";position:absolute;inset:0;background:var(--grad);z-index:-1}
.hero h1{margin:0;font-size:34px;line-height:1.15}
.hero p{margin:12px 0 0;max-width:640px;color:rgba(255,255,255,.92);font-size:16px}
.hero .hero-cta{margin-top:22px;display:flex;gap:12px;flex-wrap:wrap}
.btn-white{background:#fff;color:var(--primary);padding:10px 20px;border-radius:8px;font-weight:600;box-shadow:0 4px 12px rgba(0,0,0,.1)}
.btn-ghost{border:1px solid rgba(255,255,255,.4);color:#fff;padding:10px 20px;border-radius:8px}
.btn-ghost:hover{background:rgba(255,255,255,.1);text-decoration:none}
.btn-white:hover{text-decoration:none;box-shadow:0 6px 18px rgba(0,0,0,.15)}

/* Content */
main{min-height:60vh}
.section{padding:40px 0}
.article{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:24px;box-shadow:0 1px 2px rgba(0,0,0,.03);margin-bottom:18px}
.article h2{margin-top:0;font-size:22px}
.article h3{font-size:17px;margin-top:18px}
.article p, .article ul{color:#334155;font-size:15px}
.article ul{padding-left:20px}

/* Brand grid */
.brand-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:12px;margin-top:16px}
.brand-card{display:flex;align-items:center;gap:12px;background:var(--card);border:1px solid var(--border);border-radius:14px;padding:18px;transition:transform .15s,box-shadow .15s;color:var(--fg)}
.brand-card:hover{transform:translateY(-2px);box-shadow:0 6px 18px rgba(0,0,0,.06);text-decoration:none}
.brand-card .emoji{font-size:28px}
.brand-card .label{font-weight:600}
.brand-card .desc{font-size:12px;color:var(--muted)}

/* Features */
.feature-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;margin-top:24px}
.feature{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:22px}
.feature .icon{width:38px;height:38px;border-radius:10px;background:var(--grad);margin-bottom:10px}
.feature h3{margin:0;font-size:17px}
.feature p{color:var(--muted);font-size:14px;margin:6px 0 0}

/* Steps */
.steps{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:24px;margin-top:24px}
.steps h2{margin-top:0}
.steps-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:16px;margin-top:14px}
.step .num{width:34px;height:34px;border-radius:50%;background:var(--grad);color:#fff;font-weight:700;display:flex;align-items:center;justify-content:center;margin-bottom:8px}

/* FAQ */
details{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:18px;margin-bottom:10px}
details summary{cursor:pointer;font-weight:600;list-style:none;display:flex;justify-content:space-between;align-items:center}
details summary::-webkit-details-marker{display:none}
details[open] .plus{transform:rotate(45deg)}
.plus{color:var(--primary);font-size:22px;transition:transform .2s;display:inline-block}
details p{color:#475569;font-size:14px;margin:10px 0 0}

/* CTA */
.cta-box{margin-top:36px;padding:36px 24px;color:#fff;text-align:center;border-radius:18px;background:var(--grad);box-shadow:var(--shadow)}
.cta-box h2{margin:0;font-size:24px}
.cta-box p{margin:10px auto 0;max-width:520px;color:rgba(255,255,255,.92)}

/* Codes gate */
.gate{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:22px;margin-top:18px}
.gate-progress{height:8px;background:#e2e8f0;border-radius:99px;overflow:hidden;margin:12px 0 18px}
.gate-progress > div{height:100%;background:var(--grad);width:0;transition:width .3s}
.gate .tip{background:#f0f9ff;border:1px solid #bae6fd;border-radius:10px;padding:14px;font-size:14px;color:#0c4a6e;margin-bottom:14px}
.gate .actions{display:flex;justify-content:space-between;align-items:center;gap:10px;flex-wrap:wrap}
.btn-primary{background:var(--grad);color:#fff;border:none;padding:10px 24px;border-radius:8px;font-weight:600;cursor:pointer;font-size:15px}
.btn-primary:disabled{opacity:.5;cursor:not-allowed}
.btn-primary:hover:not(:disabled){box-shadow:var(--shadow)}
.code-list{display:grid;gap:10px;margin-top:14px}
.code-item{display:flex;justify-content:space-between;align-items:center;background:#f8fafc;border:1px solid var(--border);border-radius:10px;padding:14px;gap:12px;flex-wrap:wrap}
.code-item .code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-weight:700;color:var(--primary);font-size:15px}
.code-item .reward{font-size:13px;color:var(--muted)}
.copy-btn{background:#fff;border:1px solid var(--border);padding:6px 14px;border-radius:6px;cursor:pointer;font-size:13px}
.copy-btn:hover{background:#e0f2fe;border-color:var(--primary);color:var(--primary)}
.brand-tag{display:inline-block;background:#e0f2fe;color:var(--primary);font-size:11px;font-weight:600;padding:2px 8px;border-radius:99px;margin-right:8px}

/* Ads */
.ad-wrap{margin:18px auto;min-height:90px}

/* Footer */
.site-footer{background:#f1f5f9;border-top:1px solid var(--border);margin-top:40px;padding-top:32px}
.footer-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px;padding-bottom:24px}
.footer-grid h3{margin:0 0 6px;font-size:16px}
.footer-grid p{color:var(--muted);font-size:14px;max-width:480px;margin:0}
.footer-links{display:flex;flex-wrap:wrap;gap:14px;justify-content:flex-end;align-items:flex-start;font-size:14px}
.footer-links a{color:var(--muted)}
.copy{text-align:center;font-size:12px;color:var(--muted);padding:16px 0}

@media (max-width:720px){
  .hero h1{font-size:26px}
  .nav-links{font-size:12px;gap:2px;overflow-x:auto;flex-wrap:nowrap;width:100%}
  .nav-links a{padding:5px 9px;white-space:nowrap}
  .footer-grid{grid-template-columns:1fr}
  .footer-links{justify-content:flex-start}
}