/* Palette and base */
:root{
  --bg:#F7F4F1; /* 象牙白基底 */
  --ink:#2b2730; /* 深紫灰文字 */
  --muted:#6e6a72;
  --accent:#3f3750; /* 深紫灰偏色 */
  --line:rgba(47,43,50,0.08);
  --card-bg:#ffffff;
  --radius:6px;
  --gap:18px;
}
*{box-sizing:border-box}
html,body{height:100%;margin:0;font-family:Georgia, 'Times New Roman', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;background:var(--bg);color:var(--ink);-webkit-font-smoothing:antialiased}
.page-wrap{padding:28px 20px 60px}
/* Header: 极简细导航 + 双层窄导航 */
.site-header{padding:10px 20px 6px}
.header-top{display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);padding-bottom:8px}
.brand{font-weight:700;color:var(--accent);text-decoration:none;font-size:18px}
.tiny-nav{font-size:12px;color:var(--muted);display:flex;gap:12px}
.header-secondary{font-size:13px;padding-top:8px}
.header-secondary ul{display:flex;gap:14px;list-style:none;margin:0;padding:4px 0}
.header-secondary li span{color:var(--muted);border-bottom:1px solid transparent;padding-bottom:4px}
.header-secondary li span:hover{border-bottom-color:var(--line)}

/* Article head: 标题与摘要左右分置 */
.article{max-width:1400px;margin:18px auto}
.article-head{display:flex;align-items:flex-start;gap:20px;padding:6px 12px}
.article-head h1{font-size:24px;margin:0;font-weight:700;line-height:1.18;color:var(--ink);}
.summary{margin-left:auto;max-width:420px;color:var(--muted);font-size:14px;border-left:1px solid var(--line);padding-left:16px}

.meta-row{display:flex;gap:12px;align-items:center;padding:8px 12px 0;font-size:13px;color:var(--muted)}
.meta-row time{white-space:nowrap}

/* Ads containers must be independent */
.ad-slot{background:transparent;padding:12px 0;max-width:100%}
.ad-slot > *{display:block}

/* Layout grid: 主区9/3分栏 */
.layout-grid{display:grid;grid-template-columns:1fr;gap:22px;padding:12px}
.main-column{min-width:0}
.side-column{order:2}

/* Content surface: 方角框线、局部底色 */
.body-surface{background:var(--card-bg);border:1px solid var(--line);padding:18px;border-radius:var(--radius)}
.content{color:var(--ink);line-height:1.8;font-size:16px}
.content p{margin:0 0 14px}
/* visual_signature: 正文首段轻量首字强调 */
.content p:first-of-type::first-letter{font-size:1.65em;font-weight:600;color:var(--accent);float:left;line-height:1;margin-right:6px}

/* FAQ pattern: 无卡片 details 折叠列表 */
.faq-section{margin-top:18px}
.faq-list details{border-top:1px solid var(--line);padding:10px 0}
.faq-list details:first-child{border-top:none}
.faq-list summary{cursor:pointer;font-weight:600;color:var(--accent);list-style:none;outline:none}
.faq-list summary::-webkit-details-marker{display:none}
.faq-list details p{margin:8px 0 0;color:var(--muted)}

/* Side blocks: 细线和小字号标签 */
.side-column{display:flex;flex-direction:column;gap:12px}
.side-block{background:transparent;border:1px solid var(--line);padding:12px;border-radius:var(--radius);font-size:13px}
.side-title{margin:0 0 8px;font-size:13px;color:var(--muted)}
.tags{font-size:13px;color:var(--accent);word-break:break-word}
.meta-small .meta-line{color:var(--muted);font-size:12px}

/* Related: 底部三列短卡但不用阴影 */
.related-block{padding-top:18px}
.related-grid{display:grid;grid-template-columns:1fr 1fr 1fr;gap:12px}
.related-grid > *{background:var(--card-bg);border:1px solid var(--line);padding:10px;border-radius:4px;font-size:14px}

/* Footer */
.site-footer{border-top:1px solid var(--line);padding:14px 20px;color:var(--muted);font-size:13px;text-align:center}

/* Desktop rules - must include @media (min-width:1024px) */
@media (min-width:1024px){
  .page-wrap{padding:36px 40px}
  .article{max-width:1280px;margin:20px auto}
  .header-secondary{display:block}
  .layout-grid{grid-template-columns:3fr 1fr;gap:24px;align-items:start}
  .main-column{order:1}
  .side-column{order:2}
  .article-head h1{font-size:28px}
  .content{font-size:17px}
  .summary{font-size:15px}
  /* denser info: small labels and tight spacing */
  .side-block{font-size:13px;padding:10px}
  .related-grid{grid-template-columns:repeat(3,1fr)}
}

/* Mobile rules - must include @media (max-width:767px) */
@media (max-width:767px){
  .header-secondary{display:none} /* 取消第二层横排导航 */
  .page-wrap{padding:16px 12px}
  .article-head{flex-direction:column;align-items:flex-start}
  .summary{border-left:none;padding-left:0;margin-top:8px}
  .meta-row{flex-direction:column;align-items:flex-start;gap:6px}
  .layout-grid{grid-template-columns:1fr;gap:16px}
  .side-column{order:3}
  .main-column{order:1}
  .content{font-size:16px}
  .content p{margin-bottom:14px}
  .related-grid{grid-template-columns:repeat(2,1fr);gap:10px}
  .related-grid > *{font-size:13px}
  /* 标签换行，自然重排 */
  .tags{word-break:break-word}
  /* 保证在 320px 时不横向滚动 */
  body,html{overflow-x:hidden}
}

/* Mid-range screens tweak */
@media (min-width:768px) and (max-width:1023px){
  .header-secondary{display:none}
  .layout-grid{grid-template-columns:1fr;gap:18px}
  .related-grid{grid-template-columns:repeat(2,1fr)}
}

/* Accessibility & small utilities */
h1,h2,h3{color:var(--ink);margin:0}
.section-title{font-size:16px;margin:8px 0;color:var(--accent)}
a{color:inherit}