div里的文字左右居中 上下居中

<style type="text/css">
#MrJin_b {
position:relative;
text-align:center;
}
</style>

<div id="MrJin_b">
<a href="http://www.baidu.com/">测试内容</a>
</div>

<style type="text/css">
#div-a{
height:60px;
line-height:60px;
background-color:#999;
}
</style>

<div id="div-a">
aaaaaaaa
</div>

<style type="text/css">
#MrJin {
position:static;
*position:relative;
height:300px;
width:500px;
border:1px solid #03c;
*display:block!important;
display:table!important;
}
#MrJin_a {
position:static;
*position:absolute;
display:table-cell;
vertical-align:middle;
*display:block;
top:50%;
width:100%;
}
#MrJin_b {
position:relative;
top:-50%;
text-align:center;
width:100%;
}
</style>

<div id="MrJin">
<div id="MrJin_a">
<div id="MrJin_b"> <a href="http://www.baidu.com/">测试内容</a> </div>
</div>
</div>