<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<section>
<h3>Two Individual Images</h3>
<div>
<a class="example-image-link" href="http://lokeshdhakar.com/projects/lightbox2/images/image-1.jpg" data-lightbox="example-1"><img class="example-image" src="http://lokeshdhakar.com/projects/lightbox2/images/thumb-1.jpg" alt="image-1" /></a>
<a class="example-image-link" href="http://lokeshdhakar.com/projects/lightbox2/images/image-2.jpg" data-lightbox="example-2" data-title="Optional caption."><img class="example-image" src="http://lokeshdhakar.com/projects/lightbox2/images/thumb-2.jpg" alt="image-1"/></a>
</div>
<hr />
<h3>A Four Image Set</h3>
<div>
<a class="example-image-link" href="http://lokeshdhakar.com/projects/lightbox2/images/image-3.jpg" data-lightbox="example-set" data-title="Click the right half of the image to move forward."><img class="example-image" src="http://lokeshdhakar.com/projects/lightbox2/images/thumb-3.jpg" alt=""/></a>
<a class="example-image-link" href="http://lokeshdhakar.com/projects/lightbox2/images/image-4.jpg" data-lightbox="example-set" data-title="Or press the right arrow on your keyboard."><img class="example-image" src="http://lokeshdhakar.com/projects/lightbox2/images/thumb-4.jpg" alt="" /></a>
<a class="example-image-link" href="http://lokeshdhakar.com/projects/lightbox2/images/image-5.jpg" data-lightbox="example-set" data-title="The next image in the set is preloaded as you're viewing."><img class="example-image" src="http://lokeshdhakar.com/projects/lightbox2/images/thumb-5.jpg" alt="" /></a>
<a class="example-image-link" href="http://lokeshdhakar.com/projects/lightbox2/images/image-6.jpg" data-lightbox="example-set" data-title="Click anywhere outside the image or the X to the right to close."><img class="example-image" src="http://lokeshdhakar.com/projects/lightbox2/images/thumb-6.jpg" alt="" /></a>
</div>
</section>