This is an example of a responsive thumbnail gallery with pop out images using the w3schools-CSS .
Tips: For best results make sure all the thumbnail images source are same size in each row.
If you are getting scroll bars at the side with your embed code make the embed box (height) longer.
There are many ways of displaying images using custom CSS. However, the effect is only viewable within the created embed container box that holds the code.
update 2022: Google sites now have a full embed page . Back soon for a demo!
Click on an image !