向Bootstrap导航栏添加响应功能
要将响应功能添加到导航栏，需要折叠的内容需要使用类.collapse，.navbar-collapse包裹在<div>中。
您可以尝试运行以下代码来
示例
<!DOCTYPE html>
<html>
<head>
<title>Bootstrap Example</title>
<link href = "/bootstrap/css/bootstrap.min.css" rel = "stylesheet">
<script src = "/scripts/jquery.min.js"></script>
<script src = "/bootstrap/js/bootstrap.min.js"></script>
</head>
<body style="background: #F5CBA7;">
<nav class = "navbar navbar-default" role = "navigation">
<div class = "navbar-header">
<button type = "button" class = "navbar-toggle"
data-toggle = "collapse" data-target = "#example-navbar-collapse">
<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 = "#">Tools</a>
</div>
<div class = "collapse navbar-collapse" id = "example-navbar-collapse">
<ul class = "nav navbar-nav">
<li class = "active"><a href = "#">Online Compiler</a></li>
<li><a href = "#">Image Editor</a></li>
<li class = "dropdown">
<a href = "#" class = "dropdown-toggle" data-toggle = "dropdown">
Whiteboard
<b class = "caret"></b>
</a>
<ul class = "dropdown-menu">
<li><a href = "#">Image Optimizer</a></li>
</ul>
</li>
</ul>
</div>
</nav>
</body>
</html>