:root{
  --bg:#f5f7fb;
  --ink:#0b1220;
  --muted:#5b6679;
  --brand:#1b55ff;
  --brand-2:#22c55e;
  --card:#ffffff;
  --line:#e7ecf6;
  --shadow:0 16px 40px rgba(15,23,42,.08);
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family:"Microsoft YaHei","PingFang SC","Noto Sans SC",Arial,sans-serif;
  background:var(--bg);
  color:var(--ink);
  line-height:1.65;
}
img{max-width:100%;display:block}
img,svg{height:auto}
a{color:inherit;text-decoration:none}
.wrap{max-width:1200px;margin:0 auto;padding:0 20px}
*{min-width:0}

.topbar{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.9);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.topbar-inner{display:flex;align-items:center;justify-content:space-between;gap:18px;height:72px}
.logo{height:40px;width:auto}
.main-nav{display:flex;gap:12px;align-items:center}
.main-nav a{padding:8px 14px;border-radius:999px;font-weight:700;border:1px solid transparent}
.main-nav a:hover{background:#eef3ff;border-color:#d7e4ff;color:var(--brand)}
.nav-cta{background:var(--brand);color:#fff;border-color:var(--brand)}
.nav-toggle{display:none;border:none;background:#0f172a;color:#fff;width:40px;height:40px;border-radius:12px;font-size:20px}

.hero-a{padding:54px 0 24px}
.hero-a-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:32px;align-items:center}
.tag{display:inline-flex;background:#e7f0ff;color:#1b55ff;padding:6px 12px;border-radius:999px;font-weight:700}
.hero-a-copy h1{font-size:34px;line-height:1.2;margin:10px 0}
.hero-a-copy p{max-width:640px}
.hero-a-copy p{color:var(--muted)}
.cta-row{display:flex;gap:12px;margin:16px 0}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:10px 18px;border-radius:12px;font-weight:700;border:1px solid #d7e4ff}
.btn.primary{background:var(--brand);color:#fff;border-color:var(--brand)}
.btn.ghost{background:#fff;color:var(--brand)}
.keyword-strip{display:flex;flex-wrap:wrap;gap:8px}
.keyword-strip span{background:#fff;border:1px dashed #d9e3f6;color:#3c4a64;border-radius:10px;padding:6px 10px;font-size:12px}
.hero-a-media{position:relative}
.hero-a-media img{border-radius:24px;box-shadow:var(--shadow)}
.hero-stack{position:absolute;right:14px;bottom:-16px;background:#0f172a;color:#fff;border-radius:14px;padding:10px 12px;box-shadow:0 16px 30px rgba(2,8,20,.25)}
.hero-stack div{font-size:12px;color:#c7d2fe}

.ribbon{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin:8px auto 28px}
.ribbon-item{background:#0f172a;color:#e2e8f0;border-radius:14px;padding:12px;text-align:center;font-weight:700}

.section{padding:28px 0}
.section-title{margin-bottom:16px}
.section-title h2{margin:0 0 6px;font-size:24px}
.section-title p{margin:0;color:var(--muted)}

.portal-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.portal-grid article{background:var(--card);border-radius:16px;padding:16px;border:1px solid var(--line);box-shadow:var(--shadow)}
.portal-grid article p{word-break:break-word}
.portal-grid a{color:var(--brand);font-weight:700}

.split{display:grid;grid-template-columns:1fr 1fr;gap:28px;align-items:center}
.split-media img{border-radius:22px;box-shadow:var(--shadow)}
.list{padding-left:18px;color:var(--muted)}

.risk-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.risk-card{background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px;font-weight:700}
.risk-card{line-height:1.5}

.coin-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px}
.coin{background:#fff;border-radius:16px;padding:12px;text-align:center;border:1px solid var(--line);box-shadow:var(--shadow)}
.coin img{width:34px;height:34px;margin:0 auto 8px}

.faq-list details{background:#fff;border:1px solid var(--line);border-radius:14px;padding:12px 14px;margin-bottom:10px;box-shadow:var(--shadow)}
.faq-list summary{font-weight:700;cursor:pointer}

.site-footer{background:#0f172a;color:#e2e8f0;margin-top:40px}
.footer-grid{display:grid;grid-template-columns:minmax(260px,1.3fr) repeat(3,minmax(170px,1fr));gap:20px;padding:26px 0}
.footer-grid a{display:block;color:#cbd5f5;margin:6px 0;font-size:13px}
.foot-brand p{color:#9fb3d9;margin:6px 0 0}
.copy{border-top:1px solid rgba(255,255,255,.08);padding:12px 0;color:#a9b6d3;font-size:12px}

.drawer{position:fixed;top:88px;left:50%;transform:translate(-50%,-10px);width:min(92vw,420px);background:#fff;border-radius:20px;box-shadow:0 24px 60px rgba(15,23,42,.2);padding:16px;opacity:0;pointer-events:none;transition:.2s;z-index:90;display:none}
.drawer-head{display:flex;align-items:center;justify-content:space-between;font-weight:700;margin-bottom:10px}
.drawer-close{border:none;background:#0f172a;color:#fff;border-radius:10px;width:34px;height:34px;font-size:18px}
.drawer-links{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.drawer-links a{padding:10px;border-radius:12px;background:#f2f6ff;border:1px solid #e4ecff;text-align:center;font-weight:600}
.drawer-actions{display:grid;gap:10px;margin-top:10px}
.scrim{position:fixed;inset:0;background:rgba(10,20,40,.45);opacity:0;pointer-events:none;transition:.2s;z-index:80;display:none}
.nav-open .drawer{opacity:1;transform:translate(-50%,0);pointer-events:auto}
.nav-open .scrim{opacity:1;pointer-events:auto}
.nav-open{overflow:hidden}

/* interaction polish */
.portal-grid article,
.risk-card,
.coin,
.faq-list details {
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.portal-grid article:hover,
.risk-card:hover,
.coin:hover,
.faq-list details:hover {
  transform: translateY(-4px);
  box-shadow: 0 18px 40px rgba(15,23,42,.12);
  border-color: #cfe0ff;
}
.main-nav a.active{background:#eef3ff;border-color:#d7e4ff;color:var(--brand)}


@media (max-width:1024px){
  .hero-a-grid,.split{grid-template-columns:1fr}
  .portal-grid{grid-template-columns:repeat(2,1fr)}
  .coin-grid{grid-template-columns:repeat(4,1fr)}
  .risk-grid{grid-template-columns:repeat(2,1fr)}
  .ribbon{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:900px){
  .main-nav{display:none}
  .nav-toggle{display:inline-flex;align-items:center;justify-content:center}
  .drawer,.scrim{display:block}
}
@media (min-width:901px){
  .nav-toggle{display:none}
  .drawer,.scrim{display:none}
}
@media (max-width:820px){
  .wrap{padding:0 16px}
  .hero-a-copy h1{font-size:30px}
  .hero-a-media img{border-radius:20px}
  .portal-grid{grid-template-columns:1fr}
  .coin-grid{grid-template-columns:repeat(3,1fr)}
}
@media (max-width:640px){
  .topbar-inner{height:64px}
  .logo{height:36px}
  .hero-a{padding:36px 0 16px}
  .hero-a-grid{gap:20px}
  .hero-a-copy h1{font-size:26px}
  .cta-row{flex-direction:column}
  .keyword-strip{gap:6px}
  .hero-a-media{order:-1}
  .hero-stack{position:static;margin-top:10px}
  .ribbon{grid-template-columns:1fr;margin-bottom:20px}
  .portal-grid{grid-template-columns:1fr}
  .split{gap:18px}
  .risk-grid{grid-template-columns:1fr}
  .coin-grid{grid-template-columns:repeat(2,1fr)}
  .drawer{
    top:68px;
    left:50%;
    right:auto;
    width:92%;
    max-width:360px;
    transform:translateX(-50%) translateY(-10px);
    border-radius:18px;
    max-height:62vh;
    overflow:auto;
    -webkit-overflow-scrolling:touch;
    padding:12px 12px 14px;
  }
  .drawer-links{grid-template-columns:1fr;gap:8px}
  .drawer-links a{
    padding:12px 14px;
    font-size:15px;
    text-align:left;
    white-space:nowrap;
    overflow:hidden;
    text-overflow:ellipsis;
  }
  .drawer-actions{gap:8px}
  .nav-toggle{width:44px;height:44px;border-radius:14px}
  .portal-grid article,.risk-card,.coin,.faq-list details{border-radius:16px}
}
@media (max-width:420px){
  .wrap{padding:0 12px}
  .topbar-inner{gap:10px}
  .logo{height:32px}
  .hero-a-copy h1{font-size:24px}
  .btn{padding:10px 14px}
  .coin-grid{grid-template-columns:repeat(2,1fr)}
  .drawer{max-width:100%}
}