div居中怎么弄
<style>
.a{border:1px solid red;height:50px;}
.b{border:1px solid blue;float:left;}
.c{border:1px solid green;float:left;}
</style>
<div class="a">
<div class="b">bbbbbbbbbbbbbbbbb</div>
<div class="c">ccccccccccccccccc</div>
</div>
<style>
.a{border:1px solid red;height:50px;}
.b{padding-left:12px;padding-right:12px;border:1px solid blue;}
.c{border:1px solid green;float:left;}
.d{width:300px;margin:0 auto;}
.b,.c{text-align:center;}
</style>
<div class="a">
<div class="d">
<div class="b">bbbbbbbbbbbbbbbbb</div>
<div class="c">ccccccccccccccccc</div>
</div>
</div>
