I've been down this rabbit hole a few times when trying to go from an orgmode document to something I can share with other people. Usually, the path took me via html and then to pdf.
My initial impression was that the opening sentence is underselling the project:
Casual-Markdown-Doc provide a quick solution to use markdown as document.
I believe the word document is not clear here, for clarity's sake I would suggest expanding it to describe what are the potential outputs (... to use markdown directly as a ready to publish html website?)