How to modify font family (etc.) of rendered Markdown in notebook

[yuuuxt]

How to modify font family (and font size, font weight if possible) of rendered Markdown contents in notebook?

I haven't found a setting or a related issue yet.

Also, I want to modify how a notebook looks further. Is there a css file available for that purpose?

[rebornix]

We currently don't have a setting to override the font family for markdown previews in notebook. Good feature request.