Looking at the page source shows that it is vanilla JS [1] with a few libraries:

* https://anseki.github.io/leader-line/

* https://barba.js.org/docs/getstarted/intro/

* https://swiperjs.com/

[1]: https://uclab.fh-potsdam.de/arete/assets/js/application.js

thanks, looks like it's leader-line that does most of the layout. I couldn't find it earlier on google, but now I see that was because the helpful AI had some stuff about fishing and I missed it.