[pie_flavor]

You're pulling the old man card on CSS-in-JS? Putting your style logic in CSS is what CSS is for, CSS-in-JS is an annoying hack to make React work. What this is replacing is SCSS.

[masswerk]

Well, historically, styles were first in JS (JS StyleSheets in Netscape 4.0) and were pulled out into CSS. – This is an old man card! ;-)