JSFiddle - React, Tailwind, and code Playground

HTML

<div>
Foo bar baz
</div>

CSS

@media (max-width: 30em) {
  div {
    background: red;
  }
}

/* Why doesn't this work? 🤔 */
@media (width <= 30em) {
  body div {
    background: blue;
  }
}