<html>
<style type="text/css">
.list {width: 130px; height: 14px;}
.close {width: 130px; height: 1px; overflow: hidden;}
.open {width: 130px; height: auto; overflow: visible;}
</style>
<script language="JavaScript">
function ListOnClick()
{
var d = document.getElementById("List01");
d.className = (d.className == 'open')?'close':'open';
}
</script>
<body>
<DIV class="list" onClick="ListOnClick()">
<span class="menu_main">Раздел</span><br>
</DIV>
<DIV id="List01" class="close">
<a class="menu" href="#">1й пункт</a><br>
<a class="menu" href="#">2й пункт</a><br>
<a class="menu" href="#">3й пункт</a>
</DIV>
</body>
</html>