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<html>
<head>
<style>
body{font-family:arial;}
table{background:black;position:absolute;}
a{color:black;text-decoration:none;font:bold}
a:hover{color:#606060}
td.menu{background:lightgreen}
table.topnav{font-size:80%;top:0;left:0}
table.menu{font-size:100%;bottom:0;z-index:-1}
</style>
<script type="text/javascript">
var i=0
var c=0
var intHide
function show_hide_menu()
{
if (c==0)
	{
	clearInterval(intHide)
	intShow=setInterval("show()",10)
	c=1
	}
else
	{
	clearInterval(intShow)
	intHide=setInterval("hide()",10)
	c=0
	}
}
function show()
{
if (i>-100)
	{
	i=i-1
	document.all("menu").style.bottom=i
	}
}
function hide()
{
if (i<0)
	{
	i=i+1
	document.all("menu").style.bottom=i
	}
}
</script>

</head>
<body>

<table class="topnav" width="150">
<tr>
<td bgcolor="#FF0000" onclick="show_hide_menu()">
<b>MENU</b><br />
<table class="menu" id="menu" width="100%">
<tr><td class="menu"><a href="/html/index.asp">HTML</a></td></tr>
<tr><td class="menu"><a href="/xhtml/index.asp">XHTML</a></td></tr>
<tr><td class="menu"><a href="/css/index.asp">CSS</a></td></tr>
<tr><td class="menu"><a href="/xml/index.asp">XML</a></td></tr>
<tr><td class="menu"><a href="/xsl/index.asp">XSL</a></td></tr>
</table>
</td>
</tr>
</table>

<p>请点击 MENU，您会看到菜单的选项。</p>

</body>
</html>

W3School TIY Editor