:root {
  --bg: #f7f8fa;
  --panel: #ffffff;
  --border: #e2e5ea;
  --text: #1f2430;
  --muted: #6b7280;
  --accent: #4e79a7;
  --danger: #e15759;
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

html, body {
  margin: 0;
  height: 100%;
  font-family: -apple-system, "Segoe UI", "Microsoft YaHei", Roboto, "Helvetica Neue", sans-serif;
  color: var(--text);
  background: var(--bg);
  font-size: 14px;
}

body { display: flex; flex-direction: column; overflow: hidden; }

/* ---------------- 顶部工具栏 ---------------- */
.toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 18px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  flex: 0 0 auto;
}
.title h1 { margin: 0; font-size: 16px; font-weight: 650; }
.subtitle { font-size: 12px; color: var(--muted); }
.controls { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.btn {
  padding: 6px 12px;
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 6px;
  cursor: pointer;
  font-size: 13px;
  color: var(--text);
}
.btn:hover { background: #f0f2f5; }
.btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }
#search {
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 13px;
  width: 180px;
}
.mini {
  border: none; background: none; cursor: pointer;
  color: var(--muted); font-size: 12px; padding: 2px 6px;
}
.mini:hover { color: var(--danger); }

/* ---------------- 主体 ---------------- */
.main { display: flex; flex: 1 1 auto; min-height: 0; }

/* 侧边筛选 */
.sidebar {
  width: 200px;
  flex: 0 0 auto;
  background: var(--panel);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 12px;
}
.filter-head {
  display: flex; justify-content: space-between; align-items: center;
  font-weight: 650; margin-bottom: 4px;
}
.filter-group { margin-bottom: 14px; }
.filter-group h3 { font-size: 12px; color: var(--muted); margin: 8px 0 4px; text-transform: uppercase; letter-spacing: .04em; }
.chk { display: flex; align-items: center; gap: 6px; padding: 2px 0; cursor: pointer; font-size: 13px; }
.chk input { cursor: pointer; }
.chk .dot { width: 10px; height: 10px; border-radius: 50%; display: inline-block; flex: 0 0 auto; }
.chk .cnt { color: var(--muted); font-size: 11px; margin-left: auto; }


.filter-toggle { cursor: pointer; user-select: none; display: flex; justify-content: space-between; align-items: center; }
.filter-toggle::after { content: "▾"; font-size: 9px; color: var(--muted); }
.filter-group.collapsed .filter-toggle::after { content: "▸"; }
.filter-group.collapsed div[id^="filter-"] { display: none; }
.legend .legend-head { font-weight: 650; cursor: pointer; }
.legend .legend-head::after { content: " ▾"; font-size: 9px; }
.legend.collapsed .legend-head::after { content: " ▸"; }
.legend.collapsed .legend-body { display: none; }

/* 图区 */
.graph-wrap {
  flex: 1 1 auto;
  position: relative;
  min-width: 0;
}
#graph { width: 100%; height: 100%; display: block; cursor: grab; }
#graph:active { cursor: grabbing; }
.hint {
  position: absolute; bottom: 10px; left: 50%; transform: translateX(-50%);
  font-size: 11px; color: var(--muted); background: rgba(255,255,255,.8);
  padding: 4px 12px; border-radius: 20px; pointer-events: none;
}
.legend {
  position: absolute; top: 10px; left: 10px;
  background: rgba(255,255,255,.92); border: 1px solid var(--border);
  border-radius: 8px; padding: 8px 10px; font-size: 12px;
}
.legend .li { display: flex; align-items: center; gap: 6px; padding: 1px 0; }
.legend .dot { width: 10px; height: 10px; border-radius: 50%; }

/* 节点 / 边 */
.link { stroke: #c9ced6; stroke-opacity: .5; }
.link.highlight { stroke: var(--accent); stroke-opacity: .9; }
.link.dim { stroke-opacity: .06; }
.node { stroke: #fff; stroke-width: 1px; cursor: pointer; }
.node.dim { opacity: .12; }
.node-label { font-size: 10px; fill: #555; pointer-events: none; text-anchor: middle; }
.node-label.dim { opacity: .12; }

/* 详情面板 */
.detail {
  width: 300px;
  flex: 0 0 auto;
  background: var(--panel);
  border-left: 1px solid var(--border);
  overflow-y: auto;
  padding: 14px;
}
.detail-empty { color: var(--muted); font-size: 13px; text-align: center; margin-top: 40px; }
.detail h2 { margin: 0 0 4px; font-size: 15px; }
.detail .meta { font-size: 12px; color: var(--muted); margin-bottom: 10px; }
.detail .qtext { font-size: 14px; line-height: 1.6; margin: 8px 0; }
.detail .qtext.en { }
.badge {
  display: inline-block; padding: 2px 8px; border-radius: 12px;
  font-size: 11px; margin: 2px 3px 2px 0; background: #eef1f5; color: #333;
}
.badge.theory { background: #e8eef7; color: #2a5b8f; }
.badge.warn { background: #fdecec; color: #b23a3c; }
.detail .sec { margin-top: 12px; }
.detail .sec h4 { margin: 0 0 6px; font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
.detail .cite { font-size: 12px; padding: 4px 0; border-top: 1px solid #f0f2f5; }
.detail .cite a { color: var(--accent); text-decoration: none; }
.detail .cite a:hover { text-decoration: underline; }

/* 指标弹层 */
.metrics-overlay {
  position: fixed; inset: 0; background: rgba(0,0,0,.35);
  display: flex; align-items: center; justify-content: center; z-index: 50;
}
.metrics-panel {
  background: #fff; border-radius: 12px; width: 560px; max-width: 92vw;
  max-height: 82vh; overflow-y: auto; padding: 18px 20px;
  box-shadow: 0 12px 40px rgba(0,0,0,.2);
}
.metrics-head { display: flex; justify-content: space-between; align-items: center; }
.metrics-head h2 { margin: 0; font-size: 16px; }
.stat-row { display: flex; gap: 16px; margin: 12px 0; flex-wrap: wrap; }
.stat {
  flex: 1; min-width: 90px; background: #f4f6f9; border-radius: 8px;
  padding: 10px 12px; text-align: center;
}
.stat .v { font-size: 22px; font-weight: 700; color: var(--accent); }
.stat .k { font-size: 11px; color: var(--muted); margin-top: 2px; }
.metrics-panel table { width: 100%; border-collapse: collapse; font-size: 13px; margin: 8px 0 16px; }
.metrics-panel th, .metrics-panel td { text-align: left; padding: 5px 8px; border-bottom: 1px solid #f0f2f5; }
.metrics-panel th { color: var(--muted); font-weight: 600; font-size: 12px; }
.metrics-panel .cluster-row { cursor: pointer; }
.metrics-panel .cluster-row:hover { background: #f4f6f9; }

/* 读图说明弹层 */
.readme-panel { width: 680px; }
.readme-body { font-size: 13px; line-height: 1.7; color: var(--text); }
.readme-body h3 { margin: 16px 0 6px; font-size: 14px; }
.readme-body p, .readme-body ul { margin: 6px 0; }
.readme-body ul { padding-left: 18px; }
.readme-body .dot { display: inline-block; width: 10px; height: 10px; border-radius: 50%; margin-right: 6px; vertical-align: middle; }
.readme-clusters { width: 100%; border-collapse: collapse; margin: 8px 0; }
.readme-clusters td { padding: 5px 8px; border-bottom: 1px solid #f0f2f5; vertical-align: top; }
.readme-clusters td:first-child { white-space: nowrap; font-weight: 600; }

/* tooltip */
.tooltip {
  position: fixed; pointer-events: none; z-index: 100;
  background: rgba(20,24,32,.94); color: #fff;
  border-radius: 8px; padding: 8px 10px; font-size: 12px;
  max-width: 320px; line-height: 1.5; box-shadow: 0 4px 16px rgba(0,0,0,.3);
}
.tooltip .t-title { font-weight: 650; margin-bottom: 2px; }
.tooltip .t-why { color: #aeb8c6; font-size: 11px; margin-top: 4px; }