JSFiddle - React, Tailwind, and code Playground

HTML

<span class="spoiler" data-target="#test1">жми</span>
<div class="spoiler-content" id="test1">
  Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean pretium posuere mollis. Nullam non aliquam lorem. Curabitur nisl felis, tristique sit amet ante vel, euismod dictum erat. Pellentesque quam massa, auctor at aliquet vel, gravida vel turpis. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Praesent at laoreet neque, id volutpat diam. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Nulla dui dolor, tempor in velit at, consequat fringilla orci.
</div>

CSS

.spoiler {
  border-bottom: dashed 3px gray;
}
.spoiler-content {
  display: none;
}
.spoiler-content.active {
  display: block;
  padding: 1em;
}

JavaScript

document.addEventListener('click', function(evt){
	if (evt.target.classList.contains('spoiler')) {
  	document.querySelector(evt.target.dataset.target).classList.toggle('active')
  }
})