A nitpick perhaps, but I was surprised to see `cite` used to enclose the author's name in your `blockquote` example. I was under the impression that `cite` is meant to be used to mark up titles of books and similar, not author names, and MDN[1] seems to agree with me here.
That aside, nice work! This could surely be useful as a default stylesheet for Markdown documents and the like.
The recommendations on markup for citation sources has changed significantly over time. Originally they said something like <blockquote>… <cite>…</cite></blockquote>, then they changed it to <blockquote>… <footer><cite>…</cite></footer></blockquote>, now they seem to be saying <figure><blockquote>…</blockquote><figcaption><cite>…</cite></figcaption></figure> Similarly what should be included in the text inside a <cite> element has changed over time.
Frankly, since the cite element has no implicit ARIA role and is normal flow and phrasing content, it’s roughly just another spelling of <i>. Don’t worry too much about its nominal semantics, they’ll probably tweak them again before long.
That aside, nice work! This could surely be useful as a default stylesheet for Markdown documents and the like.
[1] https://developer.mozilla.org/en-US/docs/Web/HTML/Element/ci...