* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: -apple-system, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif; background: #f5f7fa; color: #333; }

.topbar { display: flex; align-items: center; gap: 10px; height: 50px; padding: 0 20px; background: #409eff; color: #fff; box-shadow: 0 2px 8px rgba(0,0,0,.08); position: sticky; top: 0; z-index: 10; }
.topbar .logo { font-size: 17px; font-weight: 600; }
.topbar .sub { font-size: 12px; opacity: .85; border: 1px solid rgba(255,255,255,.5); padding: 1px 8px; border-radius: 10px; }

.layout { display: flex; min-height: calc(100vh - 50px); }

.sidebar { width: 270px; background: #fff; border-right: 1px solid #e6e6e6; padding: 14px 0; overflow-y: auto; max-height: calc(100vh - 50px); position: sticky; top: 50px; }
.sidebar .cat { font-size: 12px; color: #999; padding: 14px 18px 6px; letter-spacing: 1px; }
.sidebar a.page-link { display: block; padding: 8px 18px 8px 26px; color: #444; text-decoration: none; font-size: 14px; border-left: 3px solid transparent; transition: all .15s; }
.sidebar a.page-link:hover { color: #409eff; background: #f0f7ff; }
.sidebar a.page-link.active { color: #409eff; border-left-color: #409eff; background: #ecf5ff; font-weight: 600; }
.sidebar a.page-link[data-active="1"] { color: #409eff; border-left-color: #409eff; background: #ecf5ff; font-weight: 600; }

.content { flex: 1; padding: 30px 40px 80px; max-width: 980px; }
.content article { background: #fff; border-radius: 6px; padding: 34px 44px; box-shadow: 0 1px 4px rgba(0,0,0,.06); }

/* markdown */
.content h1 { font-size: 26px; margin: 18px 0 16px; padding-bottom: 10px; border-bottom: 1px solid #eee; }
.content h2 { font-size: 21px; margin: 26px 0 12px; color: #2c3e50; border-left: 4px solid #409eff; padding-left: 10px; }
.content h3 { font-size: 18px; margin: 20px 0 10px; }
.content h4 { font-size: 16px; margin: 16px 0 8px; color: #555; }
.content p { margin: 10px 0; line-height: 1.8; font-size: 15px; }
.content ul, .content ol { padding-left: 26px; margin: 10px 0; }
.content li { line-height: 1.9; font-size: 15px; }
.content code { background: #f4f4f5; color: #c7254e; padding: 2px 6px; border-radius: 3px; font-family: Consolas, monospace; font-size: 13px; }
.content pre { background: #282c34; color: #abb2bf; padding: 16px; border-radius: 6px; overflow-x: auto; margin: 12px 0; }
.content pre code { background: none; color: inherit; padding: 0; }
.content blockquote { border-left: 4px solid #ddd; padding: 6px 14px; color: #666; margin: 12px 0; background: #fafafa; }
.content table { border-collapse: collapse; margin: 14px 0; width: 100%; }
.content th, .content td { border: 1px solid #e0e0e0; padding: 8px 12px; font-size: 14px; text-align: left; }
.content th { background: #f5f7fa; }
.content img { max-width: 100%; border: 1px solid #eee; border-radius: 4px; margin: 8px 0; display: block; }
.content a { color: #409eff; }
.content hr { border: none; border-top: 1px solid #eee; margin: 20px 0; }
.content strong { color: #222; }

@media (max-width: 768px) {
  .layout { flex-direction: column; }
  .sidebar { width: 100%; max-height: none; position: static; }
  .content { padding: 16px; }
  .content article { padding: 20px; }
}