.kb-root {
  display: flex;
  flex-direction: column;
  height: calc(100vh - var(--topbar-h, 64px));
  min-height: 520px;
  padding: var(--sp-5);
  overflow: hidden;
}

.kb-tab,
.kb-viewer-toolbar {
  display: flex;
  align-items: center;
}

.kb-workspace {
  display: grid;
  grid-template-columns: var(--kb-sidebar-width, 280px) 0 minmax(0, 1fr);
  flex: 1;
  min-height: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--panel-strong);
  transition: grid-template-columns var(--dur-slow) var(--ease);
}

.kb-workspace.is-sidebar-resizing {
  cursor: col-resize;
  user-select: none;
  transition: none;
}

.kb-browser {
  min-width: 0;
  overflow: auto;
  background: var(--bg-raised);
  opacity: 1;
  transition: opacity var(--dur-base) var(--ease), visibility 0s linear 0s;
}

.kb-workspace.is-sidebar-collapsed .kb-browser {
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur-fast) var(--ease), visibility 0s linear var(--dur-fast);
}

.kb-search {
  position: sticky;
  top: 0;
  z-index: 2;
  width: auto;
  padding: var(--sp-3);
  background: var(--bg-raised);
}
.kb-search .global-search__icon { left: 26px; }
.kb-search .global-search__clear { right: 20px; }
.kb-tree { padding: 0 var(--sp-2) var(--sp-4); }
.kb-tree__empty { padding: var(--sp-5) var(--sp-3); text-align: center; }
.kb-tree-node { margin: 1px 0; }
.kb-tree-node__children { padding-left: 16px; }
.kb-tree-node.is-collapsed > .kb-tree-node__children { display: none; }

.kb-tree-row {
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 34px;
  padding: 5px 8px;
  gap: 7px;
  border: 0;
  border-radius: var(--r-sm);
  color: var(--text);
  background: transparent;
  text-align: left;
  cursor: pointer;
}

.kb-tree-row:hover { background: var(--panel-hover); }
.kb-tree-row.is-active { color: var(--blue); background: var(--blue-dim); }
.kb-tree-row__chevron { width: 14px; flex: 0 0 14px; transition: transform .15s ease; }
.kb-tree-node.is-collapsed > .kb-tree-row .kb-tree-row__chevron { transform: rotate(-90deg); }
.kb-tree-row__icon { width: 17px; flex: 0 0 17px; color: var(--muted); }
.kb-tree-row__name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.kb-tree-row__type { margin-left: auto; color: var(--muted); font-size: 10px; text-transform: uppercase; }

.kb-resizer {
  position: relative;
  z-index: 12;
  width: 10px;
  height: 100%;
  justify-self: center;
  outline: none;
  cursor: col-resize;
  touch-action: none;
}
.kb-resizer::before {
  content: '';
  position: absolute;
  inset: 0 auto 0 50%;
  width: 1px;
  background: transparent;
  transform: translateX(-50%);
  transition: width var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}
.kb-resizer:hover::before,
.kb-resizer:focus-visible::before,
.kb-workspace.is-sidebar-resizing .kb-resizer::before {
  width: 2px;
  background: color-mix(in srgb, var(--lime) 52%, var(--border));
}

.kb-resizer__toggle {
  position: absolute;
  top: 50%;
  left: 50%;
  display: grid;
  width: 24px;
  height: 38px;
  place-items: center;
  border: 1px solid var(--border);
  border-radius: 9px;
  color: var(--text-muted);
  background: var(--bg-raised);
  box-shadow: var(--shadow-xs);
  opacity: 0;
  transform: translate(-50%, -50%) scale(.9);
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease),
              opacity var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.kb-resizer:hover .kb-resizer__toggle,
.kb-resizer:focus-visible .kb-resizer__toggle,
.kb-workspace.is-sidebar-resizing .kb-resizer__toggle,
.kb-workspace.is-sidebar-collapsed .kb-resizer__toggle {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
}
.kb-resizer:hover .kb-resizer__toggle,
.kb-resizer:focus-visible .kb-resizer__toggle {
  border-color: color-mix(in srgb, var(--lime) 42%, var(--border));
  color: var(--lime);
}
.kb-workspace.is-sidebar-collapsed .kb-resizer { cursor: e-resize; }
.kb-workspace.is-sidebar-collapsed .kb-resizer__toggle svg { transform: rotate(180deg); }

.kb-document-area { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.kb-tabs { position: relative; z-index: 13; display: flex; min-height: 43px; overflow-x: auto; border-bottom: 1px solid var(--line); background: var(--bg-raised); }
.kb-tab { flex: 0 0 auto; max-width: 240px; gap: 7px; padding: 0 10px 0 14px; border: 0; border-right: 1px solid var(--line); color: var(--muted); background: transparent; cursor: pointer; }
.kb-tab.is-active { color: var(--text); background: var(--panel-strong); box-shadow: inset 0 -2px var(--blue); }
.kb-tab__name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.kb-tab__close {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 22px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  line-height: 1;
}
.kb-tab__close svg {
  display: block;
  width: 10px;
  height: 10px;
  overflow: visible;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
  stroke-linecap: round;
}
.kb-tab__close:hover { background: var(--panel-hover); }
.kb-viewer { position: relative; flex: 1; min-height: 0; overflow: auto; background: var(--bg); }
.kb-empty { display: grid; place-items: center; align-content: center; height: 100%; gap: var(--sp-3); color: var(--muted); text-align: center; }
.kb-viewer-frame { width: 100%; height: 100%; border: 0; background: #525659; }
.kb-viewer-toolbar { min-height: 44px; justify-content: space-between; gap: var(--sp-3); padding: 7px var(--sp-3); border-bottom: 1px solid var(--line); background: var(--panel-strong); }
.kb-viewer-toolbar__title { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.kb-viewer-content { height: calc(100% - 44px); }
.kb-text-document { min-height: 100%; margin: 0; padding: clamp(24px, 5vw, 72px); color: #1d2733; background: #fff; font: 15px/1.7 ui-monospace, SFMono-Regular, Consolas, monospace; white-space: pre-wrap; overflow-wrap: anywhere; }
.kb-loading { display: grid; place-items: center; height: 100%; color: var(--muted); }

.integration-module-row {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--r-md);
  background: var(--panel);
}
.integration-module-row--knowledge-base { flex-wrap: wrap; }
.kb-settings-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--sp-2);
  flex-wrap: wrap;
}
.kb-settings-actions #kb-settings-summary { min-width: 180px; text-align: right; }

@media (max-width: 800px) {
  .kb-root { padding: var(--sp-3); }
  .kb-workspace { grid-template-columns: 1fr; grid-template-rows: minmax(150px, 34%) minmax(0, 1fr); }
  .kb-browser { border-right: 0; border-bottom: 1px solid var(--line); }
  .kb-resizer { display: none; }
  .kb-document-area { grid-row: 2; }
  .kb-settings-actions { width: 100%; justify-content: flex-start; padding-left: 48px; }
  .kb-settings-actions #kb-settings-summary { min-width: 0; text-align: left; }
}