I have been having excellent luck with MkDocs Material. It’s very lightweight and static and has a ton of extensibility. Their documentation itself is written using their own software and gives you a great idea of what it has to offer: squidfunk.github.io/mkdocs-material/

I use it both at work and for a game squadron wiki. It’s entirely written in Markdown so syntax is pretty quick to learn as well. Not sure if this is exactly what you’re looking for, but it’s become my new go to for documentation.