bootstrap 4 w3schools

<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">

npm install bootstrap

 <!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">

 
<!-- jQuery library -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>


  <!-- Popper JS -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.0/umd/popper.min.js"></script>

 
<!-- Latest compiled JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script> 

    <button class="btn btn-primary">
  <span class="spinner-border 
    spinner-border-sm"></span>
</button>

<button class="btn 
    btn-primary">
  <span class="spinner-border 
    spinner-border-sm"></span>
  Loading..
</button>

<button 
    class="btn btn-primary" disabled>
  <span class="spinner-border 
    spinner-border-sm"></span>
  Loading..
</button>

    
<button class="btn btn-primary" disabled>
  <span 
    class="spinner-grow spinner-grow-sm"></span>
  Loading..

    </button>
 

 <button type="button" class="btn btn-primary btn-block">Full-Width 
  Button</button> 

bootstrap

Bootstrap 4 is the newest version of Bootstrap, which is the most popular HTML, CSS, and JavaScript framework for developing responsive, mobile-first websites.

Bootstrap 4 is completely free to download and use!

See below link