.toc dt {
  background: url(nav-tree-leaf.gif) left 1px no-repeat;
  padding-left: 15px;
}
.toc .opened {
  background: url(nav-tree-minus.gif) left 1px no-repeat;
  padding-left: 15px;
}
.toc .closed {
  background: url(nav-tree-plus.gif) left 1px no-repeat;
  padding-left: 15px;
}
.toc-hidden {
  display: none;
}