Documentation is written in mkdocs and there are a few extensions that allow richer authoring than markdown.
To iterate with documentation, therefore, it is recommended to run the mkdocs server and view your pages in a browser.
If running on an arm64-based mac (M1 or M2, aka "Applie Silicon"), you may find this method quite slow. Until multiarch docker images can be built and made available, you may wish to build your own via:
git clone git@github.com:squidfunk/mkdocs-material.git
docker build -t docker.io/squidfunk/mkdocs-material .