Exercise:

Make the alert message closable.

Hint: Add class="alert-dismissible" to the alert container and class="close" and data-dismiss="alert" to the <a> element.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="../../maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
  <script src="../../ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
  <script src="../../maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>

<div class="container">
  <div class="alert alert-success alert-dismissible">
    <a href="#" class="close" data-dismiss="alert" aria-label="close">&times;</a>
    <strong>Success!</strong> This alert box could indicate a successful or positive action.
  </div>
</div>

</body>
</html>