[SPBS]

TL;DR the author settled on Tailwind. I prefer Tachyons myself (less overhead). I agree that functional/atomic CSS is the way to go.

Separation Of Concerns (HTML <-> CSS) is a LIE. Naming is one of the hardest things in computer science, and folks in the "Separation Of Concerns" camp repeatedly subject themselves to this torture by forcing themselves to come up with "semantic" names instead of just writing the damn styles and seeing which styles get repeatedly used together so that they can be condensed into a class.