fixed vs relative font-size keywords
On page 75, there is a discussion about relative vs. fixed font sizes. Unfortunately, I got some of the facts wrong here.
It turns out that
x-large (along with
absolute-size keywords, not relative-size. So changing the base font-size will not
change elements that are styled with those keywords.
On the other hand,
smaller are relative font-size keywords, and
work as described. The specifics can be found here in the W3C's documentation.
Github user bazzaxiv was kind enough to report this and provide the reference. Thanks so much!