Sphinx and reStructuredText are, IMHO, underrated power houses of document building. With extensions, you can hook them up to Zotero (or whatever)-managed bibtex files. You can render to beautiful HTML files, and you get latex PDFs and epubs for free. First class latex-math support, plenty of integrations with things like mermaid, graphviz, and the ability to build super-powerful custom directives to do basically any…
Also works with HTML documents produced in other ways.