:root{
  --bg:#070b1a; --bg2:#0d1430; --surface:rgba(255,255,255,.045);
  --surface2:rgba(255,255,255,.07); --border:rgba(124,92,255,.22);
  --primary:#7c5cff; --accent:#22d3ee; --gold:#f5c542; --green:#34d399;
  --text:#e8ecf8; --muted:#9aa6c4; --danger:#fb7185;
  --radius:16px; --maxw:1120px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
  background:var(--bg); color:var(--text); line-height:1.75; font-size:16px;
  background-image:
    radial-gradient(900px 500px at 12% -8%, rgba(124,92,255,.20), transparent 60%),
    radial-gradient(800px 520px at 100% 0%, rgba(34,211,238,.14), transparent 55%),
    radial-gradient(2px 2px at 20% 30%, rgba(255,255,255,.5), transparent),
    radial-gradient(2px 2px at 70% 60%, rgba(255,255,255,.35), transparent),
    radial-gradient(1.5px 1.5px at 40% 80%, rgba(255,255,255,.4), transparent),
    radial-gradient(1.5px 1.5px at 85% 25%, rgba(255,255,255,.3), transparent),
    linear-gradient(180deg,var(--bg),var(--bg2));
  background-attachment:fixed;
}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 18px}
img{max-width:100%}
.site-header{position:sticky;top:0;z-index:50;backdrop-filter:blur(12px);
  background:rgba(7,11,26,.72);border-bottom:1px solid var(--border)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:62px}
.logo{font-weight:800;font-size:20px;color:#fff;display:flex;flex-direction:column;line-height:1.05}
.logo span{font-size:11px;font-weight:600;letter-spacing:1px;color:var(--accent)}
.nav-links{display:flex;gap:22px;align-items:center}
.nav-links a{color:var(--text);font-weight:600;font-size:15px}
.nav-links a:hover{color:var(--accent);text-decoration:none}
.nav-toggle{display:none;background:none;border:1px solid var(--border);color:#fff;
  font-size:22px;border-radius:10px;width:42px;height:38px;cursor:pointer}
.lang-switch{margin-left:14px;padding:6px 14px;border-radius:999px;border:1px solid var(--border);
  color:var(--text);font-weight:700;font-size:14px}
.lang-switch:hover{border-color:var(--accent);color:var(--accent);text-decoration:none}
.btn{display:inline-block;padding:11px 22px;border-radius:999px;font-weight:700;
  border:1px solid transparent;cursor:pointer;transition:.2s}
.btn-primary{background:linear-gradient(135deg,var(--primary),var(--accent));color:#06122b}
.btn-primary:hover{filter:brightness(1.08);text-decoration:none}
.btn-ghost{border-color:var(--border);color:var(--text)}
.btn-ghost:hover{border-color:var(--accent);text-decoration:none}
.hero{padding:64px 0 40px;text-align:center}
.hero h1{font-size:clamp(30px,5vw,52px);font-weight:900;letter-spacing:1px;
  background:linear-gradient(120deg,#fff,var(--accent) 60%,var(--primary));
  -webkit-background-clip:text;background-clip:text;color:transparent}
.hero p{color:var(--muted);font-size:18px;margin:14px auto 26px;max-width:680px}
.hero-actions{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.stats{display:flex;gap:26px;justify-content:center;flex-wrap:wrap;margin-top:36px}
.stat{text-align:center}
.stat b{display:block;font-size:26px;color:var(--gold)}
.stat span{color:var(--muted);font-size:13px}
.section{padding:40px 0}
.section h2{font-size:26px;margin-bottom:6px;font-weight:800}
.section .sub{color:var(--muted);margin-bottom:22px}
.grid{display:grid;gap:18px;grid-template-columns:repeat(auto-fill,minmax(260px,1fr))}
.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);
  padding:20px;transition:.2s}
.card:hover{background:var(--surface2);transform:translateY(-3px);border-color:var(--accent)}
.card .tag{display:inline-block;font-size:12px;font-weight:700;color:#06122b;
  background:linear-gradient(135deg,var(--accent),var(--primary));padding:3px 10px;border-radius:999px;margin-bottom:10px}
.card h3{font-size:19px;margin-bottom:8px}
.card h3 a{color:#fff}
.card p{color:var(--muted);font-size:14.5px}
.article{max-width:820px;margin:0 auto;padding:30px 0 20px}
.breadcrumb{color:var(--muted);font-size:13px;margin-bottom:14px}
.breadcrumb a{color:var(--muted)}
.article h1{font-size:clamp(26px,4vw,38px);margin-bottom:10px;font-weight:900}
.article .lead{color:var(--muted);font-size:17px;margin-bottom:24px}
.article h2{font-size:23px;margin:32px 0 12px;padding-left:12px;border-left:4px solid var(--primary)}
.article h3{font-size:18px;margin:22px 0 8px;color:var(--accent)}
.article p{margin:12px 0}
.article ul,.article ol{margin:12px 0 12px 22px}
.article li{margin:6px 0}
.callout{border:1px solid var(--border);border-left:4px solid var(--accent);
  background:var(--surface);padding:14px 16px;border-radius:12px;margin:18px 0}
.callout.tip{border-left-color:var(--green)}
.callout.warn{border-left-color:var(--danger)}
.callout b{color:#fff}
table{width:100%;border-collapse:collapse;margin:18px 0;font-size:14.5px;
  background:var(--surface);border-radius:12px;overflow:hidden}
th,td{padding:10px 12px;border-bottom:1px solid var(--border);text-align:left}
th{background:rgba(124,92,255,.18);color:#fff;font-weight:700}
tr:last-child td{border-bottom:none}
.ad-slot{border:1px dashed var(--border);border-radius:12px;padding:26px 16px;text-align:center;
  color:var(--muted);background:var(--surface);margin:26px 0;font-size:14px}
.tool-box{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);
  padding:22px;margin:18px 0}
.tool-row{display:flex;flex-wrap:wrap;gap:14px;align-items:center;margin:12px 0}
.tool-row label{min-width:140px;color:var(--text);font-weight:600}
.tool-row input,.tool-row select{flex:1;min-width:160px;padding:10px 12px;border-radius:10px;
  border:1px solid var(--border);background:#0a1024;color:#fff;font-size:15px}
.tool-result{margin-top:16px;padding:16px;border-radius:12px;background:rgba(34,211,238,.08);
  border:1px solid var(--accent)}
.tool-result b{color:var(--gold);font-size:20px}
.grade{font-size:34px;font-weight:900}
.site-footer{border-top:1px solid var(--border);margin-top:50px;padding:36px 0 24px;background:rgba(7,11,26,.6)}
.footer-grid{display:grid;gap:24px;grid-template-columns:repeat(auto-fit,minmax(180px,1fr))}
.footer-grid h4{color:#fff;font-size:15px;margin-bottom:12px}
.footer-grid a{display:block;color:var(--muted);font-size:14px;margin:6px 0}
.footer-grid a:hover{color:var(--accent)}
.footer-bottom{color:var(--muted);font-size:13px;text-align:center;margin-top:28px;padding-top:18px;border-top:1px solid var(--border)}
@media(max-width:760px){
  .nav-toggle{display:block}
  .lang-switch{margin-left:0}
  .nav-links{display:none;position:absolute;top:62px;left:0;right:0;flex-direction:column;
    background:rgba(7,11,26,.97);padding:14px 18px;gap:14px;border-bottom:1px solid var(--border)}
  .nav-links.open{display:flex}
}