very clever, particularly how the width of the equals signs below an h1 is made to match the text width using hidden overflow:
https://github.com/mrcoles/markdown-css/blob/0d00981143172aa...
https://github.com/mrcoles/markdown-css/blob/0d00981143172aa...
in the same vein as the h1 equals, i like the blockquote brackets implementation as well:
https://github.com/mrcoles/markdown-css/blob/0d00981143172aa...
It's a shame it doesn't work for copy-paste, but honestly, it's probably even easier to write a reverse-markdown script than to figure out how to do it with CSS!