I've been away from coding for a while, mainly due to Google ending Classic sites and insisting that everything works on mobiles . I gave up on all my websites for some time, being demotivated.

Classic sites are being closed by Google in 2021, so I need to get a decent slideshow system sorted for Dorsetdog.com. I find that Google's Image Carousel doesn't produce what I want from a slideshow, and neither does Google Slides. I'm still at a loss as to why they closed the brilliant Google Picasa, and Google New Sites is so restricting - but free hoasting.

I've tried a few things in the JS and CSS files (including CSS in html file) to get Jack's slideshow to shrink for mobiles, but have failed - miserably.

The slideshows files are on Github at https://github.com/jackwanders/GalleryView

My Full site demo is at http://www.dorsetdog.com/vertical-gallery-slideshow, which is built in Classic sites.

The New sites trial page is at https://sites.google.com/view/sites-toc-issues/home .
Google's new sites has various problems, including that their Table Of Contents doesn't work when it's a single page site.

Any pointers to get Jack's Galleryview slideshow to fit in a mobile phone screen would be greatly appreciated

Many thanks