:root{
  --us-brand-700:#1258c7; --us-brand-600:#1f6feb; --us-brand-500:#3d8bff;
  --us-accent-500:#ff7e5f; --us-bg-canvas:#f5f8ff; --us-surface-card:#ffffff;
  --us-surface-muted:#f0f4ff; --us-text-primary:#102040; --us-text-secondary:#4a5a7a;
  --us-border-muted:#d8e2fa; --us-shadow-soft:0 8px 24px rgba(0,0,0,.08);
  --us-shadow-pop:0 18px 40px rgba(0,0,0,.12);
  --us-font-sans:"Space Grotesk","Noto Sans SC","PingFang SC",sans-serif;
  --shell-header-height:80px;
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:var(--us-font-sans);background:var(--us-bg-canvas);color:var(--us-text-primary);-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
button{font-family:inherit;cursor:pointer;border:none;background:none}
input,textarea,select{font-family:inherit}
.hidden{display:none!important}

/* ===== Header ===== */
.app-header{position:sticky;top:0;z-index:50;height:var(--shell-header-height);display:flex;align-items:center;gap:18px;
  padding:0 28px;background:rgba(255,255,255,.75);backdrop-filter:blur(14px);border-bottom:1px solid var(--us-border-muted)}
.logo{display:flex;align-items:center;gap:10px;font-weight:700;font-size:19px;white-space:nowrap}
.logo .badge{width:34px;height:34px;border-radius:9px;background:linear-gradient(135deg,var(--us-brand-600),var(--us-accent-500));
  display:grid;place-items:center;color:#fff;font-size:15px}
.logo small{font-size:10px;color:var(--us-text-secondary);letter-spacing:2px;display:block;font-weight:500}
.search-box{flex:1;max-width:520px;position:relative}
.search-box input{width:100%;height:44px;border-radius:12px;border:1px solid var(--us-border-muted);background:var(--us-surface-muted);
  padding:0 16px 0 42px;font-size:14px;color:var(--us-text-primary);outline:none;transition:.2s}
.search-box input:focus{border-color:var(--us-brand-500);background:#fff;box-shadow:0 0 0 4px rgba(61,139,255,.12)}
.search-box::before{content:"🔍";position:absolute;left:14px;top:12px;font-size:15px;opacity:.6}
.header-actions{margin-left:auto;display:flex;align-items:center;gap:10px}
.seg{display:flex;background:var(--us-surface-muted);border-radius:11px;padding:3px;gap:2px}
.seg button{padding:7px 14px;border-radius:9px;font-size:13px;color:var(--us-text-secondary);font-weight:500}
.seg button.active{background:#fff;color:var(--us-brand-600);box-shadow:var(--us-shadow-soft)}
.credits-chip{display:flex;align-items:center;gap:6px;padding:8px 13px;border-radius:11px;background:var(--us-surface-muted);
  font-size:13px;font-weight:600;color:var(--us-brand-700)}
.credits-chip b{color:var(--us-accent-500)}
.btn{padding:10px 18px;border-radius:11px;font-size:14px;font-weight:600;transition:.18s;white-space:nowrap}
.btn-primary{background:linear-gradient(135deg,var(--us-brand-600),var(--us-brand-500));color:#fff;box-shadow:0 6px 16px rgba(31,111,235,.28)}
.btn-primary:hover{transform:translateY(-1px);box-shadow:0 10px 22px rgba(31,111,235,.35)}
.btn-ghost{background:var(--us-surface-muted);color:var(--us-brand-700)}
.btn-ghost:hover{background:#e3ebff}
.avatar{width:38px;height:38px;border-radius:50%;background:linear-gradient(135deg,var(--us-brand-500),var(--us-accent-500));
  color:#fff;display:grid;place-items:center;font-weight:700;font-size:14px;cursor:pointer}

/* ===== Tabs ===== */
.tabs{display:flex;gap:8px;padding:20px 28px 4px;overflow-x:auto;scrollbar-width:none}
.tabs::-webkit-scrollbar{display:none}
.tab{padding:9px 16px;border-radius:11px;font-size:13.5px;font-weight:600;color:var(--us-text-secondary);
  background:var(--us-surface-card);border:1px solid var(--us-border-muted);white-space:nowrap;transition:.16s}
.tab:hover{border-color:var(--us-brand-500);color:var(--us-brand-600)}
.tab.active{background:linear-gradient(135deg,var(--us-brand-600),var(--us-brand-500));color:#fff;border-color:transparent;box-shadow:0 6px 16px rgba(31,111,235,.25)}

/* ===== Sections & cards ===== */
.container{padding:12px 28px 60px;max-width:1500px;margin:0 auto}
.section-title{font-size:17px;font-weight:700;margin:26px 0 14px;display:flex;align-items:center;gap:9px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:18px}
.card{background:var(--us-surface-card);border:1px solid var(--us-border-muted);border-radius:16px;padding:18px;
  display:flex;flex-direction:column;gap:11px;transition:.2s;position:relative;overflow:hidden}
.card:hover{transform:translateY(-3px);box-shadow:var(--us-shadow-pop);border-color:#bcd0f7}
.card .star{position:absolute;top:14px;right:15px;color:var(--us-accent-500);font-size:14px}
.card .icon{width:52px;height:52px;border-radius:13px;background:var(--us-surface-muted);display:grid;place-items:center;font-size:26px}
.card h3{font-size:15.5px;font-weight:700}
.card .tags{display:flex;flex-wrap:wrap;gap:5px}
.card .tag{font-size:11px;padding:3px 8px;border-radius:7px;background:var(--us-surface-muted);color:var(--us-brand-700);font-weight:500}
.card p{font-size:12.5px;color:var(--us-text-secondary);line-height:1.55;flex:1}
.card .actions{display:flex;gap:8px;margin-top:4px}
.card .actions .btn{flex:1;padding:9px 0;text-align:center;font-size:13px}

/* ===== Modal / Auth ===== */
.overlay{position:fixed;inset:0;background:rgba(16,32,64,.5);backdrop-filter:blur(3px);display:grid;place-items:center;z-index:100;padding:20px}
.modal{background:#fff;border-radius:20px;padding:32px;width:100%;max-width:420px;box-shadow:var(--us-shadow-pop);animation:pop .2s}
@keyframes pop{from{transform:scale(.95);opacity:0}}
.modal h2{font-size:22px;margin-bottom:6px}
.modal .sub{font-size:13px;color:var(--us-text-secondary);margin-bottom:20px}
.field{margin-bottom:14px}
.field label{font-size:13px;color:var(--us-text-secondary);display:block;margin-bottom:6px;font-weight:500}
.field input{width:100%;height:46px;border-radius:12px;border:1px solid var(--us-border-muted);padding:0 14px;font-size:14.5px;outline:none;transition:.18s}
.field input:focus{border-color:var(--us-brand-500);box-shadow:0 0 0 4px rgba(61,139,255,.12)}
.modal .btn-primary{width:100%;padding:13px;margin-top:6px}
.switch-line{text-align:center;font-size:13px;color:var(--us-text-secondary);margin-top:16px}
.switch-line a{color:var(--us-brand-600);font-weight:600;cursor:pointer}
.msg{font-size:13px;margin-top:12px;text-align:center}
.msg.err{color:#e5484d}.msg.ok{color:#30a46c}

/* ===== Detail (iframe) ===== */
.detail-bar{display:flex;align-items:center;gap:14px;padding:14px 28px;background:#fff;border-bottom:1px solid var(--us-border-muted)}
.detail-bar .back{cursor:pointer;font-size:14px;color:var(--us-text-secondary);font-weight:600}
.detail-bar h2{font-size:16px;flex:1}
.frame-wrap{height:calc(100vh - 80px - 66px);background:#fff}
.frame-wrap iframe{width:100%;height:100%;border:none}

/* ===== Packages ===== */
.pkg-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:20px;margin-top:20px}
.pkg{border:1.5px solid var(--us-border-muted);border-radius:18px;padding:26px;background:#fff;position:relative;transition:.2s}
.pkg:hover{transform:translateY(-4px);box-shadow:var(--us-shadow-pop)}
.pkg.featured{border-color:var(--us-brand-500);box-shadow:0 12px 30px rgba(31,111,235,.15)}
.pkg .ribbon{position:absolute;top:-11px;right:20px;background:var(--us-accent-500);color:#fff;font-size:11px;padding:4px 12px;border-radius:8px;font-weight:600}
.pkg h3{font-size:17px}
.pkg .price{font-size:34px;font-weight:800;margin:12px 0 2px;color:var(--us-brand-700)}
.pkg .price span{font-size:14px;font-weight:500;color:var(--us-text-secondary)}
.pkg ul{list-style:none;margin:16px 0;display:flex;flex-direction:column;gap:9px}
.pkg li{font-size:13px;color:var(--us-text-secondary);display:flex;gap:8px}
.pkg li::before{content:"✓";color:var(--us-brand-600);font-weight:700}
.pkg .btn{width:100%;text-align:center;padding:12px}

/* ===== Toast ===== */
.toast{position:fixed;bottom:28px;left:50%;transform:translateX(-50%);background:var(--us-text-primary);color:#fff;
  padding:12px 22px;border-radius:12px;font-size:14px;z-index:200;box-shadow:var(--us-shadow-pop);animation:pop .18s}
.center-page{max-width:900px;margin:0 auto;padding:40px 28px}
.empty{text-align:center;color:var(--us-text-secondary);padding:60px 0;font-size:14px}