JSFiddle - React, Tailwind, and code Playground
HTML
<div id="galleryImage">
<ul>
<li>
<a href= "#">
<img src="http://placehold.it/350x150" title="The artist van" alt="The artist van"/></a>
</li>
</ul>
</div>
CSS
.active {
border:solid 3px red;
}
JavaScript
$('#galleryImage img').click(function() {
$(this).addClass('active');
});