_static/collapsible-lists/css/tree_view.css

/* Source taken directly from:
 *     view-source:http://code.iamkate.com/javascript/collapsible-lists/
 *
 * Kate Morley's license for this code is CC0:
 *     Created by [Kate Morley](http://iamkate.com/). Except where explicitly
 *     stated otherwise, all content is released under the terms of the
 *     [CC0 1.0 Universal legal code](http://creativecommons.org/publicdomain/zero/1.0/legalcode).
 */
.treeView{
  -moz-user-select:none;
  position:relative;
}

.treeView ul{
  margin:0 0 0 -1.5em ! important;
  padding:0 0 0 1.5em ! important;
}

.treeView ul ul{
  background:url('list-item-contents.png') repeat-y left ! important;
}

.treeView li.lastChild > ul{
  background-image:none ! important;
}

.treeView li{
  margin:0 ! important;
  padding:0 ! important;
  background:url('list-item-root.png') no-repeat top left ! important;
  list-style-position:inside ! important;
  list-style-image:url('button.png') ! important;
  cursor:auto;
}

.treeView li.collapsibleListOpen{
  list-style-image:url('button-open.png') ! important;
  cursor:pointer;
}

.treeView li.collapsibleListClosed{
  list-style-image:url('button-closed.png') ! important;
  cursor:pointer;
}

.treeView li li{
  background-image:url('list-item.png') ! important;
  padding-left:1.5em ! important;
}

.treeView li.lastChild{
  background-image:url('list-item-last.png') ! important;
}

.treeView li.collapsibleListOpen{
  background-image:url('list-item-open.png') ! important;
}

.treeView li.collapsibleListOpen.lastChild{
  background-image:url('list-item-last-open.png') ! important;
}