It would be nice if we had the html for some of the flip content, especially for the a/b content
They were giving pretty reasonable and, I dare say, obvious feedback. The site should provide an HTML snippet like just about every other demo page out there.
I can't see the author disagreeing with that.
You could copy and paste your "fuck them, right? /s" snark on just about every bit of feedback everywhere. I don't think that's very constructive, and it demonstrates a misreading of the parent comment.
Clicking on the icon `{.}` will slide out a div that contains the code for the CSS animation.