下面的代码中的文字无法垂直居中，请问如何解决？
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>无标题文档</title>
<style type="text/css">
<!--
#menu {
background-color: #FFFFFF;
float: none;
position: absolute;
height: 20px;
width: 427px;
top: 112px;
left: 14px;
}
#menu ul {
clear: left;
text-align: center;
margin: 0px;
padding: 0px;
border: 0px;
list-style-type: none;
display:inline;
}
#menu li {
margin: 0px;
float: left;
display: block;
text-align: center;
width: 70px;
height: 19px;
background-color: #ED8B13;
font-weight: bold;
color: #FFFFFF;
border-left: #FFFFFF 1px solid;
border-top: #FFFFFF 1px solid;
}
#menu li a {
display: block;
font-weight: bold;
color: #337BFF;
background-color: #DBEAFF;
height: 19px;
text-decoration: none;
}
#menu li a:hover {
font-weight: bold;
color: #FFFFFF;
background-color: #337BFF;
}
-->
</style>
</head>
<body
<div id="menu">
<ul>
<li>电影首页</li>
<li><a title="网吧联盟" href="netbar/index.asp">网吧联盟</a></li>
<li><a title="影视联盟" href="union/index.asp">影视联盟</a></li>
<li><a title="注册会员" href="/user/reg.asp">注册会员</a></li>
<li><a title="会员专区" href="member.asp">会员专区</a></li>
<li><a title="帮助中心" href="help.asp">帮助中心</a></li>
</ul>
</div>
</body>
</html>
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