<body>
<div id="fx" onmouseover="showlist()" onmouseout="hidelist()">分类</div>
<div id="menu" style="display: none;" onmouseover="showlist()" onmouseout="hidelist()">
<div class="f">家电</div>
<div class="f">数码</div>
<div class="f">手机</div>
<div class="f">衣服</div>
</div>
<script type="text/javascript">
function showlist()
{
document.getElementById("menu").style.display="block";
}
function hidelist()
{
document.getElementById("menu").style.display="none";
}
</script>
</body>