bootstrap 4 cdn

To include the Bootstrap 4 CDN in your webpage, you can use the following code:

<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" integrity="sha384-pzjw8f+ua6rlz5k1wq5s9xalxkz2tn0wqj3q6p4fjz8z6meh5z8fz5n5u6k5z5n5" crossorigin="anonymous">
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js" integrity="sha384-pzjw8f+ua6rlz5k1wq5s9xalxkz2tn0wqj3q6p4fjz8z6meh5z8fz5n5u6k5z5n5" crossorigin="anonymous"></script>

This code includes the Bootstrap 4 CSS and JavaScript files from the Bootstrap CDN. It ensures that your webpage will have the necessary styles and functionality provided by Bootstrap 4.

Please note that the integrity and crossorigin attributes in the code are used for security and should not be modified.