Why should you be proud to fail CSSLint?
I do as well
CSSLint does not even try to say anything about cutesy things like that. It is intended for different use cases and it is to be expected that a CSS Nyan Cat would fail CSSLint. There is nothing wrong with that, even if you believe that CSSLint is great.
I think its more nonsensical to get worked up about the fact he wrote it
Don't use IDs in selectors. #nyanCat {
What's the thinking behind disallowing ids in selectors?
what does this even mean?