重置ztree样式

// ztree样式；
/* 新的文档目录 */
.doc-tree li span.button.ico_open {
	background: url("../../images/small.png") no-repeat scroll -268px -99px transparent;
	width: 15px;
	vertical-align:top; *vertical-align:middle;
}
.doc-tree li span.button.ico_close {
	background: url("../../images/small.png") no-repeat scroll -282px -99px transparent;
	width: 15px;
	vertical-align:top; *vertical-align:middle;
}
.doc-tree li span.button.ico_docu {
	background: url("../../images/small.png") no-repeat scroll -296px -99px transparent;
	width: 15px;
	vertical-align:top; *vertical-align:middle;
}
.doc-tree li .curSelectedNode span.button.ico_docu {
	background: url("../../images/small.png") no-repeat scroll -297px -99px transparent;
	width: 15px;
	vertical-align:top; *vertical-align:middle;
}
.doc-tree li span.button.chk.checkbox_true_full,
.doc-tree li span.button.chk.checkbox_true_full_focus {
	background: url("../../images/small.png") no-repeat scroll -268px -87px transparent;
	width: 12px;
	height: 12px;
}
.doc-tree li span.button.chk.checkbox_false_full,
.doc-tree li span.button.chk.checkbox_false_full_focus {
	background: url("../../images/small.png") no-repeat scroll -279px -87px transparent;
	width: 12px;
	height: 12px;
}
.doc-tree li span.button.chk.checkbox_true_part,
.doc-tree li span.button.chk.checkbox_true_part_focus {
	background: url("../../images/small.png") no-repeat scroll -290px -87px transparent;
	width: 12px;
	height: 12px;
}
/* [-][+]收缩按钮样式修改为三角形 */
.doc-tree li span.button.center_open,
.doc-tree li span.button.bottom_open,
.doc-tree li span.button.roots_open {
	background: url("../../images/small.png") no-repeat scroll -302px -87px transparent;
	height: 12px;
	width: 12px;
	margin-left: 4px;
}
.doc-tree li span.button.center_close,
.doc-tree li span.button.bottom_close,
.doc-tree li span.button.roots_close {
	background: url("../../images/small.png") no-repeat scroll -312px -87px transparent;
	height: 12px;
	width: 12px;
	margin-left: 4px;
}