.tree-expanded{
	display:inline-block;
	width:16px;
	height:18px;
	vertical-align:middle;
	background:url('images/tree_arrows.gif') no-repeat -18px 0px;
}
.tree-expanded-hover{
	background:url('images/tree_arrows.gif') no-repeat -50px 0px;
}
.tree-collapsed{
	display:inline-block;
	width:16px;
	height:18px;
	vertical-align:middle;
	background:url('images/tree_arrows.gif') no-repeat 0px 0px;
}
.tree-collapsed-hover{
	background:url('images/tree_arrows.gif') no-repeat -32px 0px;
}