.seo-home { padding: 80px 0; background: var(--bg-white); }
.seo-grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 20px; }
.seo-card { color: var(--text-primary); text-decoration: none; border: 1px solid var(--border-color); border-radius: 16px; background: var(--bg-light); padding: 28px; display: flex; flex-direction: column; gap: 14px; }
.seo-card h3 { font-size: 20px; line-height: 1.5; }
.seo-card p { color: var(--text-secondary); font-size: 15px; line-height: 1.9; }
.seo-card span { color: var(--primary-color); margin-top: auto; }
.seo-card:hover { border-color: var(--primary-color); box-shadow: var(--shadow-sm); }
.platform-guide { color: var(--primary-color); font-size: 14px; margin-top: 18px; text-underline-offset: 4px; }
.guide-header { max-width: 1160px; margin: auto; padding: 20px 24px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--border-color); }
.guide-header .nav-brand { text-decoration: none; }
.guide-header nav { display: flex; flex-wrap: wrap; gap: 22px; }
.guide-header nav a, .breadcrumbs a, .guide-footer a { color: var(--primary-color); text-decoration: none; }
.guide-main { max-width: 1040px; margin: 0 auto; padding: 45px 24px 72px; }
.guide-main article { max-width: 820px; margin: auto; }
.breadcrumbs { color: var(--text-secondary); font-size: 14px; margin-bottom: 36px; }
.guide-kicker { color: var(--primary-color); font-size: 14px; font-weight: 600; margin-bottom: 14px; }
.guide-main h1 { font-size: clamp(30px,4vw,44px); line-height: 1.4; margin-bottom: 22px; text-wrap: balance; }
.guide-intro { font-size: 18px; color: var(--text-secondary); line-height: 1.9; }
.guide-updated { font-size: 13px; color: var(--text-secondary); margin-top: 18px; }
.guide-main article section { margin-top: 42px; scroll-margin-top: 24px; }
.guide-main article h2 { font-size: 24px; line-height: 1.5; margin-bottom: 18px; }
.guide-main article section p { font-size: 17px; line-height: 2; margin-bottom: 16px; }
.guide-toc, .guide-notice { margin-top: 30px; border: 1px solid var(--border-color); border-radius: 14px; padding: 24px 28px; background: var(--bg-light); }
.guide-toc ol { padding-left: 24px; margin-top: 12px; }
.guide-toc li { margin: 8px 0; }
.guide-toc a { color: var(--primary-color); text-underline-offset: 4px; }
.guide-notice p { margin: 10px 0 18px; color: var(--text-secondary); }
.guide-related { border-top: 1px solid var(--border-color); padding-top: 40px; margin-top: 50px; }
.guide-related h2 { margin-bottom: 24px; }
.guide-related .seo-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
.guide-actions { display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; margin-top: 40px; }
.guide-footer { border-top: 1px solid var(--border-color); padding: 28px 24px; display: flex; flex-wrap: wrap; justify-content: center; gap: 24px; font-size: 14px; }
.sitemap-list { padding-left: 24px; margin-top: 28px; }
.sitemap-list li { margin: 18px 0; }
.sitemap-list a { color: var(--primary-color); }
a:focus-visible { outline: 3px solid var(--primary-light); outline-offset: 4px; }
@media(max-width: 850px) { .seo-grid { grid-template-columns: repeat(2,minmax(0,1fr)); } .guide-header { flex-direction: column; align-items: flex-start; } }
@media(max-width: 560px) { .seo-grid, .guide-related .seo-grid { grid-template-columns: 1fr; } .seo-home { padding: 55px 0; } .guide-main { padding: 30px 20px 50px; } .guide-header nav { gap: 18px; font-size: 14px; } .guide-toc,.guide-notice { padding: 20px; } .guide-main article section p { font-size: 16px; } }