<!DOCTYPE html>
<html>
<head>
<title>Bootstrap实例</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://apps.bdimg.com/libs/bootstrap/3.3.0/css/bootstrap.min.css">
<script src="https://libs.baidu.com/jquery/2.1.4/jquery.min.js"></script>
<script src="https://apps.bdimg.com/libs/bootstrap/3.3.0/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<h2>Alerts</h2>
<p>The a element with class="close" and data-dismiss="alert" is used to close the alert box.</p>
<div class="alert alert-success">
<a href="#" class="close" data-dismiss="alert" aria-label="close">×</a>
<strong>Success!</strong> This alert box could indicate a successful or positive action.
</div>
<div class="alert alert-info">
<a href="#" class="close" data-dismiss="alert" aria-label="close">×</a>
<strong>Info!</strong> This alert box could indicate a neutral informative change or action.
</div>
<div class="alert alert-warning">
<a href="#" class="close" data-dismiss="alert" aria-label="close">×</a>
<strong>Warning!</strong> This alert box could indicate a warning that might need attention.
</div>
<div class="alert alert-danger">
<a href="#" class="close" data-dismiss="alert" aria-label="close">×</a>
<strong>Danger!</strong> This alert box could indicate a dangerous or potentially negative action.
</div>
</div>
</body>
</html>