jQuery鼠标悬浮效果，显示并隐藏层详解

<div class="listtitle fl width120">
								<div id="word_select_value_list" class="listtitle-in">
									office 2007
								</div>
								<input id="word_select_value" value="2007" type="hidden">
								<div style="width: 126px; display: none;" id="bigdiv" class="listtitle-cont2">
									<a href="javascript:getWordSelectType('2007');">office 2007</a>
									<a href="javascript:getWordSelectType('2010');">office 2010</a>
									<a href="javascript:getWordSelectType('2003');">office 2003</a>
								</div>
							</div>

//显示下拉框	
	$("#word_select_value_list").mouseover(function() {
		$(".listtitle-cont2").show();
	}).mouseout(function() {
		$(".listtitle-cont2").hide();
	});
	
	$(".listtitle-cont2").mouseover(function(){
		$(this).show();
	}).mouseout(function() {
		$(this).hide();
	});