Repository-specific styles & data (resource for contributors)

This issue will serve as a storage location for stylistic data used in this repository, e.g. figure fonts, color palettes etc. until/unless a better location presents itself.

The [Carpentries Venn Diagram](https://github.com/carpentries/instructor-training/blob/gh-pages/fig/carpentries-venn-diagram_20200904.svg):
- Font name is Adobe Courier
- font size is 8pt and it is bold

Carpentries brand colors (not consistently used in this repository but handy for new contributions) may be found here: https://docs.carpentries.org/topic_folders/communications/resources/brand_identity.html?highlight=hexcode

The issue names no file, test, or entry point. Review the linked Carpentries Venn diagram and brand-identity resource first; the issue does not define a concrete change or a clear completion criterion for the proposed repository-specific style data.

Written by the indexing model from the issue text.