/* ===== AI 资讯汇 前台样式 ===== */
:root {
  --bg: #f6f7fb;
  --surface: #ffffff;
  --text: #1f2430;
  --muted: #6b7280;
  --border: #e6e8ef;
  --primary: #2f6df6;
  --primary-dark: #1f4fd0;
  --accent: #12b981;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(16,24,40,.06), 0 8px 24px rgba(16,24,40,.05);
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: 1120px; margin: 0 auto; padding: 0 18px; }
.muted { color: var(--muted); }

/* Header */
.site-header { background: var(--surface); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 20; }
.header-inner { display: flex; align-items: center; gap: 16px; padding: 14px 18px; flex-wrap: wrap; }
.brand { font-size: 22px; font-weight: 800; color: var(--text); display: flex; align-items: center; gap: 8px; }
.brand:hover { text-decoration: none; }
.brand-logo { height: 30px; width: auto; max-width: 200px; object-fit: contain; border-radius: 4px; }
.brand-sub { color: var(--muted); font-size: 13px; flex: 1; min-width: 160px; }
.search-box { display: flex; gap: 8px; }
.search-box input { padding: 8px 12px; border: 1px solid var(--border); border-radius: 999px; width: 220px; max-width: 50vw; font-size: 14px; }
.search-box button { padding: 8px 16px; border: 0; border-radius: 999px; background: var(--primary); color: #fff; cursor: pointer; font-size: 14px; }
.search-box button:hover { background: var(--primary-dark); }
.site-nav { background: var(--surface); border-bottom: 1px solid var(--border); }
.site-nav .container { display: flex; gap: 18px; flex-wrap: wrap; padding-top: 6px; padding-bottom: 6px; }
.site-nav a { color: var(--text); font-size: 14px; padding: 6px 2px; }
.site-nav a:hover { color: var(--primary); text-decoration: none; }

/* Breadcrumb */
.breadcrumb { font-size: 13px; color: var(--muted); margin: 0 0 16px; }
.breadcrumb ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; padding: 0; margin: 0; align-items: center; }
.breadcrumb li { display: inline-flex; align-items: center; }
.breadcrumb li:not(:last-child)::after { content: "›"; margin: 0 6px; color: var(--border); }
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--primary); text-decoration: none; }
.breadcrumb [aria-current="page"] { color: var(--text); font-weight: 600; }

/* Layout */
.main-grid { display: grid; grid-template-columns: 1fr 300px; gap: 28px; padding-top: 26px; padding-bottom: 40px; align-items: start; }
@media (max-width: 900px) { .main-grid { grid-template-columns: 1fr; } }

.page-title { font-size: 22px; margin: 0 0 18px; }
.empty { color: var(--muted); padding: 30px; text-align: center; background: var(--surface); border-radius: var(--radius); }

/* Post cards */
.post-list { display: flex; flex-direction: column; gap: 16px; }
.post-card {
  display: flex; gap: 16px; background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 16px; box-shadow: var(--shadow); transition: transform .15s ease;
}
.post-card:hover { transform: translateY(-2px); }
.post-cover { width: 180px; height: 122px; object-fit: cover; border-radius: 10px; flex-shrink: 0; background: #eef1f6; }
.post-body { min-width: 0; }
.post-title { font-size: 18px; margin: 0 0 8px; line-height: 1.4; }
.post-title a { color: var(--text); }
.post-title a:hover { color: var(--primary); text-decoration: none; }
.post-meta { display: flex; gap: 12px; flex-wrap: wrap; font-size: 12.5px; color: var(--muted); margin-bottom: 6px; align-items: center; }
.post-cat { color: var(--accent); font-weight: 600; }
.post-summary { margin: 0; color: #3b4252; font-size: 14px; }
@media (max-width: 560px) { .post-card { flex-direction: column; } .post-cover { width: 100%; height: 160px; object-fit: cover; display: block; } }

/* Detail */
.post-detail { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow); }
.post-detail .post-title { font-size: 28px; margin: 6px 0 14px; }
.post-cover-lg { width: 100%; max-height: 380px; object-fit: cover; border-radius: 10px; margin: 12px 0 18px; }
.post-content { font-size: 16px; line-height: 1.9; word-break: break-word; }
.post-content img { max-width: 100%; border-radius: 8px; }
/* 正文视频：占满正文宽度、保持比例；深色背景避免透明/黑边突兀 */
.post-content video { max-width: 100%; height: auto; border-radius: 8px; background: #000; margin: 0 0 18px; }
/* 代码样式：行内 code 与块级 pre 必须分开定义。
   ⚠️ 坑：只给 code 设浅色底、却不设文字色，当它嵌在深色 pre 里时会继承 pre 的浅色文字
   → 浅灰底 + 浅白字，对比度趋近 1:1，肉眼完全不可读。 */
.post-content code {
  background: #eef1f6; color: #101828; padding: 2px 6px; border-radius: 6px;
  font-family: Consolas, Menlo, "Courier New", monospace; font-size: 13.5px;
  word-break: break-word;
}
.post-content pre {
  background: #0f172a; color: #e2e8f0;
  font-family: Consolas, Menlo, "Courier New", monospace;
  font-size: 13px; line-height: 1.8; letter-spacing: .2px;
  padding: 15px 17px; margin: 0 0 18px; border-radius: 10px;
  overflow-x: auto; white-space: pre-wrap; word-break: break-word; overflow-wrap: anywhere;
}
/* 关键：pre 内的 code 必须透明底 + 继承浅色文字（此规则特异性高于上面的 code 规则） */
.post-content pre code {
  background: transparent; color: inherit; padding: 0; border: 0; border-radius: 0;
  font-size: inherit; letter-spacing: inherit;
}

/* 正文表格：微信来源的表格常只带 table 级内联样式，th/td 没有内边距与边框，
   不兜底会挤成一团。内联样式优先级更高，此处只影响缺样式的单元格。 */
.post-content table { width: 100%; max-width: 100%; border-collapse: collapse; margin: 0 0 18px; font-size: 13.5px; }
.post-content th, .post-content td {
  border: 1px solid var(--border); padding: 8px 10px;
  text-align: left; vertical-align: top; line-height: 1.7;
}
.post-content th { background: #f4f6fb; color: var(--text); font-weight: 700; }

/* 引用块：微信正文的 blockquote 多为裸标签，浏览器默认只剩缩进 */
.post-content blockquote {
  margin: 0 0 18px; padding: 12px 16px; background: #f7f9fc; color: #334155;
  border-left: 4px solid var(--primary); border-radius: 0 8px 8px 0;
}
.post-content blockquote p:last-child { margin-bottom: 0; }
.source { margin-top: 18px; font-size: 13px; color: var(--muted); }
.related { margin-top: 28px; }
.related h3 { font-size: 18px; }
.tag-cloud { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0; }
.tag { display: inline-block; padding: 4px 12px; background: #eef2ff; color: var(--primary-dark); border-radius: 999px; font-size: 13px; }
.tag:hover { background: #e0e7ff; text-decoration: none; }

/* Sidebar */
.sidebar { display: flex; flex-direction: column; gap: 18px; position: sticky; top: 120px; }
.widget { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; box-shadow: var(--shadow); }
.widget h3 { margin: 0 0 12px; font-size: 15px; }
.cat-list { list-style: none; margin: 0; padding: 0; }
.cat-list li { padding: 6px 0; border-bottom: 1px dashed var(--border); }
.cat-list li:last-child { border-bottom: 0; }

/* Pagination */
.pagination { display: flex; gap: 8px; justify-content: center; margin: 26px 0; flex-wrap: wrap; }
.pagination a { padding: 8px 14px; border: 1px solid var(--border); border-radius: 8px; background: var(--surface); color: var(--text); font-size: 14px; }
.pagination a:hover { border-color: var(--primary); text-decoration: none; }
.pagination a.active { background: var(--primary); color: #fff; border-color: var(--primary); }

/* Footer */
.site-footer { background: var(--surface); border-top: 1px solid var(--border); padding: 24px 0; margin-top: 20px; text-align: center; color: var(--muted); font-size: 13px; }
.site-footer .icp { color: var(--muted); }

/* ===== 专题模块 ===== */
.topic-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 18px; }
.topic-card { display: flex; flex-direction: column; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); transition: transform .15s ease; color: var(--text); }
.topic-card:hover { transform: translateY(-2px); text-decoration: none; }
.topic-cover { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; background: #eef1f6; display: block; }
.topic-cover--empty { background: linear-gradient(135deg, #eef2ff, #e6f7f1); }
.topic-body { padding: 16px; min-width: 0; }
.topic-title { font-size: 18px; margin: 0 0 8px; line-height: 1.4; color: var(--text); }
.topic-title a { color: var(--text); }
.topic-summary { margin: 0 0 12px; color: #3b4252; font-size: 14px; }
.topic-count { font-size: 13px; color: var(--accent); font-weight: 600; }
.topic-lead { color: #3b4252; font-size: 15px; margin: 0 0 14px; }
.topic-stat { margin-top: 14px; }
.topic-detail .post-cover-lg { margin-top: 4px; }
@media (max-width: 560px) { .topic-grid { grid-template-columns: 1fr; } }