基于bootstrap实现收缩导航条

<link href="http://cdn.static.runoob.com/libs/bootstrap/3.3.7/css/bootstrap.min.css" rel="external nofollow" rel="stylesheet">

<ul class="navbar navbar-default navbar-fixed-top">

<div class="container-fluid">

<div class="navbar-header">
<a href="index.html" rel="external nofollow" class="navbar-brand">
<span class="glyphicon glyphicon-home">

<button class="navbar-toggle" data-toggle="collspan" data-target="#divNav"&gt;

<!---   navbar-toggle:【触发】按钮，会有下拉导航    data-toggle:交替执行某动作，collapse:展开和收缩
      data-target:目标对象(自己定义一个名字-->

<span class="icon-bar"&gt;</span>
<span class="icon-bar"&gt;</span>
<span class="icon-bar"&gt;</span>
<!--按钮里的内容,三条横杠-->

</button>
<!--点击按钮将显示的导航栏目-->
<div id="divNav" class="collapse nav-collapse"&gt;
 <!--这里的div的id要和上面的data-target值一致，nav-collapse就是折叠导航--->
 <ul class="nav navbar-nav"&gt;
  <li>首页</li>
  <li>菜单1</li>
  <li>菜单2</li>
  <li>菜单3</li>
 </ul>
</div>