bootstrap怎么使图片垂直居中？
<div class="mbrand">
<a href="#"><img src="img/mbarnd1.gif" class="img-responsive center-block"/></a>
<a href="#"><img src="img/mbarnd2.gif" class="img-responsive center-block"/></a>
<a href="#"><img src="img/mbarnd3.gif" class="img-responsive center-block"/></a>
<a href="#"><img src="img/mbarnd4.gif" class="img-responsive center-block"/></a>
<a href="#"><img src="img/mbarnd5.gif" class="img-responsive center-block"/></a>
</div>垂直居中需要用到vertical-align:middle
把图片添加css类img-responsive center-block
bootstrap里貌似没有可以垂直居中的样式，除了导航条里有个垂直居中 可以用绝对定位做 让margin-left值等于大框的宽度减图片的宽，高度同理