Pure CSS Image Gallery Lightbox – Octo
Octo is a pure CSS/CSS3 solution to enlarge and display grouped images in a lightbox with next/prev arrows navigation.
JavaScript & CSS gallery lightbox
Vanilla JavaScript Library For Photo Gallery Lightbox – PhotoViewerJS
PhotoViewerJS is a pure vanilla javascript library for displaying larger versions of thumbnails in a fullscreen, responsive gallery lightbox popup.
JS Library For Lightbox-like Image Gallery – ultralb
ultralb (Ultra Light Box) is a JavaScript library which allows you to organize and display images in a lightbox-like gallery.