Bootstrap——导航栏编写

<nav class="navbar navbar-default navbar-fixed-top" role="navigation">
<div class="container">
<div class="navbar-header">
<button class="navbar-toggle collapsed" aria-expanded="false" aria-controls="navbar" type="button" data-toggle="collapse" data-target="#navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#">Project name</a>
</div>
<div class="navbar-collapse collapse" id="navbar">
<ul class="nav navbar-nav">
<li class="active"><a href="#">Home</a></li>
<li><a href="#about">About</a></li>
<li><a href="#contact">Contact</a></li>
<li class="dropdown">
<a class="dropdown-toggle" aria-expanded="false" href="#" data-toggle="dropdown">Dropdown <span class="caret"></span></a>
<ul class="dropdown-menu" role="menu">
<li><a href="#">Action</a></li>
<li><a href="#">Another action</a></li>
<li><a href="#">Something else here</a></li>
<li class="divider"></li>
<li class="dropdown-header">Nav header</li>
<li><a href="#">Separated link</a></li>
<li><a href="#">One more separated link</a></li>
</ul>
</li>
</ul>
<ul class="nav navbar-nav navbar-right">
<li><a href="../navbar/">Default</a></li>
<li><a href="../navbar-static-top/">Static top</a></li>
<li class="active"><a href="./">Fixed top</a></li>
</ul>
</div><!--/.nav-collapse -->
</div>
</nav>