what is the best UI you've seen for browsing API reference documentation (on the web)? (ignore the actual quality of the text)

examples:

- rust: https://doc.rust-lang.org/std/
- ruby core: http://ruby-doc.org/core-2.6.3/
- yard: https://www.rubydoc.info/gems/yard/0.9.19
- rails: https://api.rubyonrails.org/
- one big markdown: https://github.com/GoogleChrome/puppeteer/blob/master/docs/api.md