JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.0.0-alpha.6/css/bootstrap.min.css">
<btn class="btn btn-primary">
  Hello
</btn>
<div class="text">
Hello World!
</div>

CSS

.btn:hover ~ .text {
  color: blue;
}