CSS Quine

I believe this to be the first quine implementation in CSS. It's possible that it could be considered an html quine instead, because it includes the html tags, I don't really know. Probably doesn't matter, right?

https://slexaxton.github.io/CSSCSS/

Inspired by these legends

• http://annevankesteren.nl/test/contenteditable-style.htm
• http://mathiasbynens.be/demo/css-hidden-elements