网站导航可以显示用户浏览的所属栏目路径和网站其他栏目的路径，清楚的展示整个网站的目录关系，更加方便用户点击跳转到其他栏目浏览，导航栏目的展示，有的是展示上下两级栏目，有的是三级栏目，让用户更加清楚完整的了解到网站的信息。二级栏目和三级栏目都可以用css实现的，栏目样式也可以多种多样，例如：用css实现导航下拉的三级菜单，如下图所示：

Html：
<div class="nav">
<ul class="clearfix">
<li>
<a href="index.html">
HOME                                                                                                             
</a>
</li>
<li>
<a href="product.html">
PRODUCTS     
</a>
<div class="cellbox">
                <div class="con">
                   <div class="nav-li">
                   <a href="" class="a-level">
                   M-Series Connectors
                   </a>
                       <div class="level-con">
                           <ul>
                             <li class="">
                             <a href="">M-Series Connectors</a>
                             <div class="twolevelbox">
                             <ul>
                             <li>
                             <a href="">
                             Connectors1
                             </a>
                             </li>
                             <li>
                             <a href="">
                             Connectors2
                             </a>
                             </li>
                             <li>
                             <a href="">
                             Connectors3
                             </a>
                             </li>
                             </ul>
                             </div>
                             </li>   
                             <li class="">
                             <a href="">7/8" Connectors</a>
                             <div class="twolevelbox">
                             <ul>
                             <li>
                             <a href="">
                             7/8" Connectors1
                             </a>
                             </li>
                             <li>
                             <a href="">
                             7/8" Connectors2
                             </a>
                             </li>
                             <li>
                             <a href="">
                             7/8" Connectors3
                             </a>
                             </li>
                             </ul>
                             </div>
                             </li>
                             <li class="">
                             <a href="">Circular Connector Series</a>
                             </li>
                           </ul>
                        </div>                    
                   </div>
                   <div class="nav-li">
                   <a href="" class="a-level">
                   7/8" Connectors
                   </a>
                   </div>
                   <div class="nav-li">
                   <a href="" class="a-level">
                   Circular Connector Series
                   </a>
                   </div>
               </div>
            </div>
</li>
<li>    
<a href="Services.html">
SERVICES             
</a>
</li>
</ul>
</div>
Css:

 
垂直的手风琴折叠菜单，一般可以用作后台页面的折叠菜单，或者产品页面的左侧的产品折叠菜单，作用同样是方便用户了解网站的信息，使用户便于快速的找到自己想要浏览的内容。
如下图所示：

Html:
<div class="menulist">
<div class="box">
<div class="item">
<div class="h1">My Account</div>
<div class="wrap">
<a href="">My Vouchers</a>
<a href="">My Profile</a>
<a href="">My Payment Options</a>
<a href="">My Measurements</a>
</div>
</div>
<div class="item">
<div class="h1">My Order</div>
<div class="wrap">
<a href="">My Order1</a>
<a href="">My Order2</a>
<a href="">My Order3</a>
<a href="">My Order4</a>
</div>
</div>
<div class="item">
<div class="h1">My Address</div>
<div class="wrap">
<a href="">My Address1</a>
<a href="">My Address2</a>
</div>
</div>
<div class="item">
<div class="h1">My Settings</div>
<div class="wrap">
<a href="">My Settings1</a>
<a href="">My Settings2</a>
<a href="">My Settings3</a>
<a href="">My Settings4</a>
</div>
</div>
</div>
</div>
Css:

Js:
$(".menulist .box .h1").click(function () {
    var box_ = $(this).next(".wrap");
    if (box_.is(":hidden")) {
        $(".menulist .box .h1").removeClass("on");
        $(this).addClass("on");
        $(".menulist .box .wrap").slideUp();
        $(this).next(".wrap").slideDown();
    } else {
        $(".menulist .box .h1").removeClass("on");
        $(".menulist .box .wrap").slideUp();
    }
});