Regarding adding images with links to the portfolios

Hi,
I am able to create the images with links in the portfolio using this code by creating my own html but its not working in codepen could any one tell me what’s the reason behind it. Thank you.
The HTML code is:

<div class="container">
    <div class="row">
      <div class="col-md-4">
       <a href="https://codepen.io/Preetk/pen/bRarqr" ><img src="https://statics.sportskeeda.com/wp-content/forum/uploads/2014/10/mary-kom-2-1414565821.jpg" class="images"</a>
      </div>
      <div class="col-md-4">
         <a><img src="https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSKSyJBy43enbeyz-fbDJP__jVkiZXDdozAlWK11x2JmDs-8xPXow" class="images"></a>
      </div>
      <div class="col-md-4">
         <a href="https://codepen.io/Preetk/pen/jYygGQ"><img src="http://www.portfolio.gsamdani.com/wp-content/forum/uploads/2017/11/The_Amazing_Desk.jpg" class="images"></a>
      </div>
</div>

The CSS code is:

.images{
    width: 300px;
    height: 150px;
    border-radius:3px;
		border:5px black solid;
}

This is how my codepen page appears:

THis is how my own html page appears:

I am just asking about images forget about nav bar and qualifications thank you.