How can I make the cross bar show when clicking the icon to display an image using this code snippet?
<link rel="stylesheet" href="css/lightbox.css">
<script src="js/lightbox.js"></script>
<a href="images/gallery_image/Gallery_img.png" data-lightbox="roadtrip">
<i class="fa fa-search-plus" aria-hidden="true"></i>
</a>