<div class="public-header">

<div class="public-container clearfloat">

<div class="header-logo"><a>logo</a></div>

<ul class="header-nav clearfloat">

<li class="item"><a href="">首页</a></li>

<li class="item"><a href="">案例</a></li>

<li class="item"><a href="">服务</a></li>

<li class="item"><a href="">新闻</a></li>

<li class="item"><a href="">关于</a></li>

</ul>

</div>

这个部分跟老师一样，public-container和header-nav后面一加上clearfloat，里面的内容就不显示了

这是详细

.clearfloat{

zoom:1;

}

.clearfloat{

display: block;

clear: both;

content: "";

visibility: hidden;

height:0;

}