/* SEO content pages: deliberately extends the original 51df.cn visual language. */
.sub-hero{position:relative;overflow:hidden;padding:64px 0 58px;background:linear-gradient(135deg,#effbfd 0%,#f7fcfd 65%,#fff8eb 100%);border-bottom:1px solid var(--border)}
.sub-hero::after{content:"";position:absolute;width:280px;height:280px;right:-100px;top:-120px;border-radius:50%;background:rgba(8,145,178,.08)}
.breadcrumb{position:relative;z-index:1;margin-bottom:18px;color:#667780;font-size:13px}.breadcrumb a{color:var(--primary);font-weight:700}.breadcrumb span{margin:0 8px;color:#9aa8ae}
.sub-hero h1{position:relative;z-index:1;max-width:850px;margin:0 0 18px;font-size:clamp(34px,4vw,52px);letter-spacing:-.035em}
.sub-hero .lead{position:relative;z-index:1;max-width:840px;margin:0;color:var(--muted);font-size:18px}
.page-meta{position:relative;z-index:1;margin-top:18px;display:flex;gap:18px;flex-wrap:wrap;color:#718188;font-size:13px}.page-meta time{font-weight:700;color:#46606a}
.content-wrap{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:46px;align-items:start}.article-body{min-width:0}.article-body h2{margin:42px 0 16px;font-size:30px}.article-body h3{margin:28px 0 12px;font-size:21px}.article-body p{margin:0 0 18px;color:#40535c}.article-body ul,.article-body ol{margin:0 0 22px;padding-left:1.4em;color:#40535c}.article-body li{margin:8px 0}.article-body strong{color:var(--primary-dark)}
.info-box{margin:26px 0;padding:22px 24px;border:1px solid #b8dce4;border-left:4px solid var(--primary);border-radius:14px;background:#f3fbfc;color:#38525c}.info-box strong{display:block;margin-bottom:7px;color:var(--primary-dark)}
.warn-box{margin:26px 0;padding:22px 24px;border:1px solid #f2d49d;border-left:4px solid var(--accent);border-radius:14px;background:#fffaf0;color:#72511c}.warn-box strong{display:block;margin-bottom:7px;color:#69420c}
.compare-table{width:100%;margin:22px 0 28px;border-collapse:separate;border-spacing:0;overflow:hidden;border:1px solid var(--border);border-radius:14px;font-size:14px}.compare-table th,.compare-table td{padding:14px 16px;border-bottom:1px solid var(--border);text-align:left;vertical-align:top}.compare-table th{background:#e8f8fb;color:var(--primary-dark)}.compare-table tr:last-child td{border-bottom:0}
.side-card{position:sticky;top:24px;padding:24px;border:1px solid var(--border);border-radius:18px;background:#fff;box-shadow:0 10px 32px rgba(22,78,99,.06)}.side-card h2{margin:0 0 15px;font-size:20px}.side-card p{color:var(--muted);font-size:14px}.side-links{display:grid;gap:8px;margin-top:16px}.side-links a{padding:10px 12px;border-radius:9px;color:#38525c;background:var(--page);font-size:14px;font-weight:700}.side-links a:hover{color:var(--primary-dark);background:#e0f5f8}
.topic-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.topic-card{display:block;padding:26px 24px;border:1px solid var(--border);border-radius:18px;background:#fff;box-shadow:0 7px 22px rgba(22,78,99,.05);transition:.2s ease}.topic-card:hover{transform:translateY(-3px);border-color:#9dcdd7;box-shadow:0 13px 28px rgba(22,78,99,.1)}.topic-card .tag{display:inline-flex;margin-bottom:12px;padding:4px 9px;border-radius:999px;color:var(--primary-dark);background:#dff5f9;font-size:11px;font-weight:900}.topic-card h2,.topic-card h3{margin:0 0 9px;font-size:20px}.topic-card p{margin:0;color:var(--muted);font-size:14px}
.article-list{display:grid;gap:14px}.article-link{display:grid;grid-template-columns:130px 1fr;gap:22px;align-items:center;padding:20px 22px;border:1px solid var(--border);border-radius:15px;background:#fff}.article-link .label{color:var(--primary);font-size:12px;font-weight:900;letter-spacing:.08em}.article-link h2,.article-link h3{margin:0 0 6px;font-size:19px}.article-link p{margin:0;color:var(--muted);font-size:14px}
.cta-band{margin-top:52px;padding:34px 36px;border-radius:20px;background:linear-gradient(145deg,var(--primary-dark),#0d718a);color:#d9edf1}.cta-band h2{margin:0 0 10px;color:#fff;font-size:27px}.cta-band p{margin:0 0 19px;color:#c2dde3}.cta-band .primary-action{background:var(--accent);color:#4a3108;box-shadow:none}
.footer-links{display:flex;gap:18px;flex-wrap:wrap}.footer-links a{font-size:13px}
.updated-note{margin:18px 0 0;color:#718188;font-size:13px}
@media (max-width:980px){.content-wrap{grid-template-columns:1fr}.side-card{position:static}.topic-grid{grid-template-columns:1fr 1fr}}
@media (max-width:760px){.sub-hero{padding:48px 0 44px}.sub-hero h1{font-size:36px}.sub-hero .lead{font-size:16px}.topic-grid{grid-template-columns:1fr}.article-link{grid-template-columns:1fr;gap:8px}.compare-table{display:block;overflow-x:auto}.cta-band{padding:28px 22px}}