[jamespetercook]

If I understand correctly you can still do that, just the underlying component will be adding/removing a CSS class instead of injecting the actual styles. I usually use the classnames library to help with this but obviously not a requirement (https://www.npmjs.com/package/circular-dependency-plugin) I find it's also easier to test for the presence of css classnames based on the provided props than it is to test for the presence of mutiple style rules.