Mentioned on the TUHS mailing list.
See also https://vivianvoss.net/blog/the-quiet-web for useful information about HTML/CSS,
https://vivianvoss.net/blog/the-markdown-replacement about markdown, https://mermaid.js.org/ note that some of the explanations shown when hovering over words like "age" or "find" are misplaced.
https://vivianvoss.net/blog/oklch-colour-system explains how to define light and dark colour schemes