JSFiddle - React, Tailwind, and code Playground

HTML

<button class="spoiler-button">Spoiler</button>
<div class="spoiler-block spoiler-hidden">
  hidden text
</div>

CSS

.spoiler-block {
  border: 1px solid black;
  padding: 10px;
  margin: 10px 1px;
}

.spoiler-hidden {
  display:none;
}

JavaScript

$(document).ready(function(){
    $('.spoiler-button').click(function(){
        $(this).next().toggleClass('spoiler-hidden');
    });
});