Ask HN: What are you using for non-tech, team documentation?

We have a small team (5). I'm the developer and the others are mostly non-technical.

I've been writing technical documentation with MKDocs which is great as a developer comfortable with Git and Markdown, but I now want to create a separate documentation set for client-facing, help/guide material that the other team members can contribute to.

Currently we just manage a Google Drive of docs and PDFs and it's disorganised and hard to manage.

What are other small teams using here? I'm looking for something that has some sort of editing interface, ideally can still track versioning of content, and is themeable to some extent. It could be self-hosted or a regular hosted SAAS.

What are some options?