How to use jquery generate css tree arr ？

[linjuming]

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript">
	function get_css_tree(){
		/* How to use jquery generate css tree arr ？
		arr=[
			"div.line_cont_1",
			"div.line_cont_1 h2.head_title",
			"div.line_cont_1 h2.head_title a",
			"div.line_cont_1 div.mod",
			"div.line_cont_1 div.mod ul.news_list",
			"div.line_cont_1 div.mod ul.news_list li",
			"div.line_cont_1 p",
			"div.line_cont_1 div.bottom",
			"div.line_cont_1 div.bottom div"
		];
		*/
	}
</script>

<!-- contents -->
<div class="line_cont_1">
	<h2 class="head_title"><a href="#">Lorem</a></h2>
	<div class="mod">
		<ul class="news_list">
			<li class="current">Lorem ipsum</li>
			<li>Lorem ipsum</li>
			<li>Lorem ipsum</li>
		</ul>
		<p>good morning sir</p>
	</div>
	<div class="bottom">
		<div>what are you?</div>
	</div>
</div>