going to fawn over Standard Ebooks site https://standardebooks.org for a minute here
So aside from providing beautiful ebooks of public domain books, the site is blazing fast serving pages for so many books, and it's all static pages:
https://alexcabal.com/posts/standard-ebooks-and-classic-web-tech
Then look on a page for a book. There's a render of a book with the cover, the books at like an angle and if you hover over it the book floats a little.
Turn off javascript and the pic still renders and floats a little. If you right click and say open pic in new tab just the unaltered cover comes up.
Which means all the magic to take the cover and turn into a render of a book with a floating animation is all done in CSS.
And even better, go to a typical book. Typical thickness in that render. Then go to a big book, like The History and Decline of the Roman Empire.
Look at that chonk of a book in the rendering. So each book rendering is rendered the relative thickness of the book. Just such a cool detail.
edit: Oh, and go to the feeds for books:
https://standardebooks.org/feeds
There's OPDS (the catalog feed format), and RSS and Atom. Normally, you make the mistake of going to a feed URL in your browser instead of a specific program to read feeds, and you're punished with horrible XML.
But click on any feed link here and it's the nice looking HTML like the rest of the site. Is the server determining dynamically if a browser is reading the feed or a different program? But wait, isn't the site static?
That's right, all those feeds are also good looking HTML. Just brilliant work.