:root{
  --pri:#4f46e5;--pri-d:#4338ca;--pri-l:#eef0ff;--cyan:#06b6d4;--green:#10b981;--amber:#f59e0b;
  --ink:#0f172a;--muted:#64748b;--line:#e6e8f0;--bg:#f8fafc;--card:#fff;--radius:16px;
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",sans-serif;color:var(--ink);background:var(--bg);line-height:1.8;-webkit-font-smoothing:antialiased}
a{color:var(--pri);text-decoration:none}
a:hover{text-decoration:underline}
svg{display:block}
.container{width:100%;max-width:1160px;margin:0 auto;padding:0 20px}
.btn{display:inline-flex;align-items:center;justify-content:center;height:44px;padding:0 22px;border-radius:12px;font-weight:600;font-size:15px;background:linear-gradient(135deg,var(--pri),#7c3aed);color:#fff;box-shadow:0 8px 20px rgba(79,70,229,.25)}
.btn:hover{text-decoration:none;transform:translateY(-1px)}

/* Header */
.header{position:sticky;top:0;z-index:50;background:rgba(248,250,252,.9);backdrop-filter:saturate(180%) blur(12px);border-bottom:1px solid var(--line)}
.header .container{display:flex;align-items:center;justify-content:space-between;height:64px;gap:16px}
.logo{display:flex;align-items:center;gap:10px;font-size:20px;font-weight:800;color:var(--ink)}
.logo:hover{text-decoration:none}
.logo svg{width:32px;height:32px}
.nav ul{display:flex;gap:26px;list-style:none}
.nav a{font-size:15px;color:var(--muted);font-weight:500}
.header .btn{height:38px;padding:0 18px;font-size:14px}

/* Layout */
.page{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:40px;padding:32px 20px 72px}
.crumbs{font-size:14px;color:var(--muted);margin-bottom:18px}
.crumbs ol{list-style:none;display:flex;flex-wrap:wrap;gap:6px}
.crumbs li+li::before{content:"›";margin-right:6px;color:#cbd5e1}
.crumbs a{color:var(--muted)}
article{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:40px 44px}
article h1{font-size:clamp(26px,4vw,36px);line-height:1.35;font-weight:800}
.meta{display:flex;flex-wrap:wrap;gap:16px;color:var(--muted);font-size:14px;margin:14px 0 26px;padding-bottom:22px;border-bottom:1px solid var(--line)}
.summary{background:var(--pri-l);border-left:4px solid var(--pri);border-radius:10px;padding:18px 22px;margin-bottom:28px}
.summary b{display:block;margin-bottom:6px;color:var(--pri-d)}
.summary ul{padding-left:20px}
article h2{font-size:24px;line-height:1.4;margin:40px 0 14px;padding-top:4px;scroll-margin-top:80px}
article h3{font-size:19px;margin:28px 0 10px;scroll-margin-top:80px}
article p{margin:0 0 16px;color:#1e293b}
article ul,article ol{margin:0 0 18px;padding-left:24px;color:#1e293b}
article li{margin:6px 0}
.table-wrap{overflow-x:auto;margin:0 0 20px;border:1px solid var(--line);border-radius:12px}
table{width:100%;border-collapse:collapse;font-size:15px;min-width:520px}
th,td{padding:12px 14px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
th{background:#f1f5f9;font-weight:700}
tr:last-child td{border-bottom:0}
.tip{background:#fff8eb;border:1px solid #fde7b0;border-radius:12px;padding:14px 18px;margin:0 0 20px;font-size:15px}
.tip b{color:#b45309}
.steps{counter-reset:s;list-style:none;padding:0}
.steps>li{counter-increment:s;position:relative;padding-left:44px;margin:16px 0}
.steps>li::before{content:counter(s);position:absolute;left:0;top:2px;width:30px;height:30px;border-radius:9px;background:var(--pri);color:#fff;font-weight:700;display:grid;place-items:center;font-size:15px}
.faq details{border:1px solid var(--line);border-radius:12px;padding:2px 18px;margin-bottom:10px;background:var(--bg)}
.faq summary{cursor:pointer;font-weight:600;padding:12px 0}
.faq details p{margin:0 0 14px;color:var(--muted)}
.cta-inline{margin:36px 0 8px;border-radius:16px;padding:28px;text-align:center;color:#fff;background:linear-gradient(135deg,#4f46e5,#7c3aed 60%,#06b6d4 130%)}
.cta-inline p{color:#fff;opacity:.92;margin-bottom:16px}
.cta-inline strong{display:block;font-size:20px;margin-bottom:6px}
.cta-inline .btn{background:#fff;color:var(--pri);box-shadow:none}
.related{margin-top:36px;padding-top:24px;border-top:1px solid var(--line)}
.related h2{margin-top:0}
.sources{font-size:14px;color:var(--muted)}

/* Sidebar */
aside .box{position:sticky;top:84px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px}
aside .box+.box{margin-top:20px;position:static}
aside h2{font-size:16px;margin-bottom:10px}
aside ol,aside ul{list-style:none;font-size:14px}
aside li{margin:8px 0}
aside a{color:var(--muted)}

/* Guide index */
.hub{padding:40px 20px 80px}
.hub h1{font-size:clamp(28px,4vw,40px);font-weight:800;line-height:1.3}
.hub .lead{color:var(--muted);font-size:17px;margin:12px 0 36px;max-width:720px}
.hub h2{font-size:22px;margin:36px 0 16px}
.cards{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.card{display:block;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px;color:var(--ink);transition:.2s}
.card:hover{text-decoration:none;box-shadow:0 12px 30px rgba(79,70,229,.12);transform:translateY(-3px)}
.card .tag{display:inline-block;font-size:12px;font-weight:700;color:var(--pri);background:var(--pri-l);padding:2px 10px;border-radius:999px;margin-bottom:10px}
.card h3{font-size:18px;margin-bottom:6px}
.card p{color:var(--muted);font-size:15px}

/* Footer */
.footer{background:#0f172a;color:#94a3b8;padding:40px 0 28px;font-size:14px}
.footer .cols{display:flex;flex-wrap:wrap;justify-content:space-between;gap:24px}
.footer a{color:#cbd5e1}
.footer ul{list-style:none;display:flex;flex-wrap:wrap;gap:18px}
.footer .copy{margin-top:20px;padding-top:18px;border-top:1px solid #1e293b}

@media (max-width:960px){
  .page{grid-template-columns:minmax(0,1fr)}
  aside{display:none}
}
@media (max-width:760px){
  .nav{display:none}
  article{padding:26px 20px;border-radius:12px}
  .page{padding:20px 12px 56px}
  .cards{grid-template-columns:1fr}
}