bootstrap alert will vanish after code example

Example 1: bootstrap alerts

<div class="alert alert-warning alert-dismissible fade show" role="alert">
  <strong>Holy guacamole!</strong> You should check in on some of those fields below.
  <button type="button" class="close" data-dismiss="alert" aria-label="Close">
    <span aria-hidden="true">&times;</span>
  </button>
</div>

Example 2: change size of alert bootstrap

In Bootstrap (v4 and v5), use this width modifier (w-25, w-50, w-75):

<div class="alert alert-danger w-50" role="alert">
  Here is some text!
</div>