From the article, "WRITING HTML AND CSS IN C ISN'T TOO BAD".
Um, any and all string handling in C is pretty miserable.
Emitting strings is fine, it's the parsing that sucks.
If you do it with the string functions from the standard library then yes, it is.
To be fair, the HTML and CSS in C wasn't too bad.. the Youtube scraper was also written in C and that was a lot more painful :)