While different from Styled Components, many people still consider CSS Modules to be squarely in the realm of CSS-in-JS. It literally generates a JavaScript mod

While different from Styled Components, many people still consider CSS Modules to be squarely in the realm of CSS-in-JS. It literally generates a JavaScript module that you must import into another JavaScript module in order to actually use the CSS classes you write, after all. Having some experience with CSS Modules myself, I thought they were interesting and definitely an improvement, but still left a lot to be desired. For example: needing to use a helper like `classnames` to join/toggle many dynamic classes together was very ugly and cumbersome. There is also no way to "directly" tie variable state/props to CSS rules – you're still required to use this indirection where a state/prop relies on there being a predefined class/modifier in the CSS file. e.g. font-size: ${props => props.size}px; color: ${props => props.special ? 'red' : 'blue'}; With solutions closer to the "fully JS" end of the spectrum like Styled Components, there are no extra "modifier" CSS selectors to come up with to handle the above situation.