Here's a video about styling "details" and "summary" tags with just basic HTML and CSS. That's good general information for those wanting to create Frequently Asked Questions (FAQs) webpages.
BUT WAIT… THERE'S MORE!
The video tutorial uses Whisk to show a side-by-side comparison of how the HTML / CSS works. Nice!
Awesome, works well in this video! I should probably change our FAQ pages to use this tag... (though sadly still cannot entirely remove JavaScript for it as they still need to look up the URL hash and decide if something should be open or not.)