.window {
  height: 100%;
  position: relative;
  background: var(--bg-frame);
  border: 3px solid var(--color-dark);
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  box-shadow: 10px 10px 0 rgba(0, 0, 0, 0.15);
}
.title-bar {
  position: relative;
  height: 44px;
  background: var(--bg-title);
  display: flex;
  align-items: center;
  padding: 0 16px;
  color: var(--color-dark);
  font-weight: 600;
}
.title-bar-left { display: flex; gap: 6px; }
.title-bar-left button { width: 30px; height: 30px; border-radius: 8px; }
.title-bar-tabs { display: flex; flex: 1; gap: 6px; align-items: center; padding-left: 14px; }
.tab { height: 30px; padding: 0 12px; border: var(--border); border-radius: 8px; display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--color-dark); background: var(--bg-tab-inactive); }
.tab.active { background: var(--bg-tab-active); }
.tab .x { font-size: 11px; opacity: 0.6; }
.tab-add { width: 26px; height: 26px; border-radius: 8px; }
.title-bar-sys { display: flex; gap: 14px; align-items: center; margin-left: auto; color: var(--color-dark); font-size: 13px; position: relative; z-index: 5; }
.window-body {
  display: flex;
  flex: 1;
  padding: 8px;
  gap: 8px;
  min-height: 0;
}
.pane-resizer {
  flex: 0 0 8px;
  width: 8px;
  border-radius: 999px;
  cursor: col-resize;
  background: transparent;
  position: relative;
  align-self: stretch;
}
.pane-resizer::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  border-radius: 999px;
  background: rgba(73, 70, 62, 0.22);
}
.pane-resizer:hover::before,
.pane-resizing .pane-resizer::before {
  background: rgba(108, 92, 231, 0.75);
}
.pane-resizing {
  cursor: col-resize;
  user-select: none;
}
.icon-bar { width: 48px; flex: 0 0 48px; background: var(--bg-iconbar); border: var(--border); border-radius: 12px; display: flex; flex-direction: column; align-items: center; padding: 12px 0; gap: 10px; }
.icon-bar button { width: 32px; height: 32px; background: transparent; border: 2px solid transparent; font-size: 15px; }
.icon-bar button.active { background: var(--bg-btn); border: var(--border); }
.pane {
  border: var(--border);
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.pane-left { width: 260px; background: var(--bg-explorer); }
.pane-middle { flex: 1; background: var(--bg-right); }
/* 正文栏当「缓冲垫」：拉伸器会给三栏写死宽度。窗口变宽时正文伸展补满（flex-grow）；
   窗口变窄、三栏挤不下时正文先缩、把地方让出来，保证大纲永远待在窗口里、不被挤出去（flex-shrink + min-width:0） */
.pane-middle { flex-grow: 1 !important; flex-shrink: 1 !important; min-width: 0; }
.pane-right { width: 300px; background: var(--bg-right); }
.pane-head {
  margin: 12px 16px 0;
  border: var(--border);
  border-radius: 24px;
  background: var(--pill-bg);
  padding: 6px 14px;
  text-align: center;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-dark);
}
.pane-head-pill { margin: 12px 16px 0; border: var(--border); border-radius: 24px; background: var(--pill-bg); display: flex; align-items: center; padding: 4px 6px; }
.pane-head-pill .nav { display: flex; gap: 4px; }
.pane-head-pill button { width: 26px; height: 26px; border-radius: 8px; }
.pane-head-pill .title { flex: 1; text-align: center; font-size: 14px; font-weight: 600; color: var(--color-dark); }
.pane-body {
  flex: 1;
  padding: 16px;
  overflow-y: auto;
  color: var(--color-dark);
}
.empty-hint { opacity: 0.55; font-size: 13px; line-height: 1.8; }
.explorer-header { display: flex; padding: 12px; gap: 6px; justify-content: center; }
.explorer-header button { width: 30px; height: 30px; border-radius: 8px; }
.folder-list { flex: 1; padding: 0 12px; overflow-y: auto; }
.explorer-bottom { padding: 12px 16px; display: flex; justify-content: space-between; align-items: center; color: var(--color-dark); }
.vault-info { display: flex; align-items: center; gap: 6px; font-weight: bold; font-size: 14px; }

/* 顶部标签：坐在分栏头上（具体位置由 js/tabs/tab-tracker.js 动态对齐）。标签组＝标签＋控制按钮，整组左对齐分栏、紧凑不拉满 */
.pane-tab-group { display: flex; align-items: center; gap: 6px; }
.pane-tab { height: 30px; padding: 0 12px; border: var(--border); border-radius: 8px; display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--color-dark); background: var(--bg-tab-inactive); box-sizing: border-box; white-space: nowrap; }
.pane-tab.active { background: var(--bg-tab-active); }
.pane-tab span { max-width: 150px; overflow: hidden; white-space: nowrap; text-overflow: ellipsis; }
.pane-tab .x { font-size: 11px; opacity: 0.6; cursor: pointer; }
.pane-tab-controls { display: flex; gap: 4px; }
.pane-tab-controls button { width: 26px; height: 26px; border-radius: 8px; }