创建一个红色警报框，指示在Bootstrap中执行危险操作
使用Bootstrap中的.alert-danger类创建一个红色警告框，指示危险操作。
您可以尝试运行以下代码来实现.alert-danger类-
示例
<!DOCTYPE html>
<html>
<head>
<title>Bootstrap Example</title>
<link rel = "stylesheet" href = "https://maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css">
<script src = "https://cdn.staticfile.org/jquery/3.3.1/jquery.min.js"></script>
<script src = "https://maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
</head>
<body>
<div class = "container">
<div class = "alert alert-danger">
<p>Danger!</p>
<p>Add dangerous action here...</p>
</div>
</div>
</body>
</html>