JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>
<div>
  <a href="#"> Klick mich</a>
  <p id="foo" style="display:none;">Hello World</p>
</div>

CSS

.active {
  color: red;
}

JavaScript

$('a').on('click', function(event) {
  event.preventDefault();
  $(this).toggleClass('active');
  $('#foo').toggle();
});