Sphinx is powerful and hard to beat if you're looking to generate documentation from code in multiple languages or export to multiple document formats, but it's slow and creaky and hard to hack on.
MkDocs by itself is okay, but Material for MkDocs is life-changing:
MkDocs by itself is okay, but Material for MkDocs is life-changing:
https://squidfunk.github.io/mkdocs-material/
If it does everything you need it to do, it'll make creating and editing sites much faster and with fewer opportunities to break things.