CSS ONLY LIGHTBOX - How to create a lightbox using CSS only - YouTube
GitHub - MartinvonBerg/simple-lightbox-fslight: Provides an easy was to add a Lightbox to Gutenberg videos, images, galleries and Media-with-Text-Blocks. Just intall and activate and use it. The Javascript-library fslightbox.js is used for that.
Semantic CSS3 Lightboxes | Tutorial
How to Add Lightbox in WordPress [using Plugins] - CoralNodes