:root {
  --bg: #ffffff;
  --bg-side: #f6f5f1;
  --bg-content: #ffffff;
  --text: #2b2b2b;
  --text-muted: #8a8780;
  --border: #e6e3da;
  --accent: #6b4fbb;
  --accent-soft: #efeafb;
  --broken: #c0392b;
  --graph-line: #cfcabb;
  --graph-node: #6b4fbb;
  --graph-node-current: #c0392b;
  --radius: 8px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: var(--bg);
  font-size: 15px;
  line-height: 1.7;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.topbar {
  height: 48px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 18px;
  background: var(--bg-side);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}
.brand { font-weight: 700; font-size: 16px; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand-sub { color: var(--text-muted); font-size: 12px; }

.layout {
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr) 300px;
  min-height: calc(100vh - 48px);
}

/* 左侧文件浏览器 */
.explorer {
  background: var(--bg-side);
  border-right: 1px solid var(--border);
  padding: 14px 12px;
  overflow-y: auto;
}
.side-title {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--text-muted);
  margin-bottom: 8px;
}
.filter {
  width: 100%;
  padding: 6px 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 13px;
  margin-bottom: 10px;
  background: #fff;
}
.filelist { list-style: none; margin: 0; padding: 0; }
.filelist li { margin: 1px 0; }
.filelist li a {
  display: block;
  padding: 5px 8px;
  border-radius: 6px;
  color: var(--text);
  font-size: 14px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.filelist li a:hover { background: var(--accent-soft); text-decoration: none; }
.filelist li.current a { background: var(--accent-soft); color: var(--accent); font-weight: 600; }
.filelist li.group {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--text-muted);
  margin-top: 10px;
  padding: 2px 8px;
}

/* 中间正文 */
.content { padding: 28px 40px; overflow-y: auto; }
.page { max-width: 760px; margin: 0 auto; }
.page-title { font-size: 28px; margin: 0 0 12px; line-height: 1.3; }
.tags { margin-bottom: 16px; }
.tag {
  display: inline-block;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 12px;
  padding: 2px 9px;
  border-radius: 20px;
  margin-right: 6px;
}
.page-body h1, .page-body h2, .page-body h3 { line-height: 1.4; margin-top: 1.4em; }
.page-body h2 { border-bottom: 1px solid var(--border); padding-bottom: 4px; }
.page-body blockquote {
  margin: 1em 0;
  padding: 4px 14px;
  border-left: 3px solid var(--accent);
  background: #faf9f7;
  color: #555;
}
.page-body code {
  background: #f0eee9;
  padding: 1px 5px;
  border-radius: 4px;
  font-family: "JetBrains Mono", "IBM Plex Mono", Consolas, monospace;
  font-size: 13px;
}
.page-body pre {
  background: #f0eee9;
  padding: 12px 14px;
  border-radius: 8px;
  overflow-x: auto;
}
.page-body pre code { background: none; padding: 0; }
.page-body table { border-collapse: collapse; margin: 1em 0; width: 100%; }
.page-body th, .page-body td { border: 1px solid var(--border); padding: 6px 10px; }
.page-body ul, .page-body ol { padding-left: 1.4em; }

/* 双链 */
.internal-link { color: var(--accent); border-bottom: 1px solid transparent; }
.internal-link:hover { border-bottom-color: var(--accent); text-decoration: none; }
.internal-link.broken { color: var(--broken); }

/* 右侧栏 */
.rightbar {
  background: var(--bg-side);
  border-left: 1px solid var(--border);
  padding: 14px 12px;
  overflow-y: auto;
}
.side-block { margin-bottom: 22px; }
.graph {
  width: 100%;
  height: 240px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  overflow: hidden;
}
.graph svg { display: block; width: 100%; height: 100%; }
.graph .node circle { cursor: pointer; }
.graph .node text { font-size: 10px; fill: var(--text); pointer-events: none; }
.graph .edge { stroke: var(--graph-line); stroke-width: 1; }
.graph .node.current circle { fill: var(--graph-node-current); }

.backlink-list { list-style: none; margin: 0; padding: 0; }
.backlink-list li { margin: 6px 0; font-size: 13px; }
.muted { color: var(--text-muted); font-size: 13px; }

@media (max-width: 980px) {
  .layout { grid-template-columns: 1fr; }
  .explorer, .rightbar { display: none; }
  .content { padding: 20px; }
}