Incorporate Asciidoctor-inspired styles

[evanlenz]

I would love to see the CSS styles from Asciidoctor applied to the output of xslTNG. Asciidoctor's DocBook output option would facilitate a hybrid system, where everything goes through DocBook (whether it originated from Asciidoc or elsewhere), but still looks like it came from Asciidoctor (but actually is rendered through xslTNG).

For example, see the styling on these pages, including the TOC on the right:
https://docs.asciidoctor.org/asciidoctor/latest/docbook-backend/
https://docs.asciidoctor.org/asciidoctor/latest/api/convert-files/

I welcome any clarifying questions, which would help ensure that my request is valid and well-formed, so to speak. :-)

[ndw]

I think that's a great idea. I'll take a peek at it when I have a chance, but if you get there first...

[ndw]

An experiment inspired by Evan's talk at Balisage 2022.