image-urls-in-gallery.php

<?php
$gallery = get_post_gallery( $post, false );
$ids = explode( ",", $gallery['ids'] );
         
foreach( $ids as $id ) {
    $link   = wp_get_attachment_url( $id );
    $image  = wp_get_attachment_image( $id, "thumbnail");
    echo( "<div class='item'><a href='$link'>" . $image . "</a></div>" );
}
?>