JSFiddle - React, Tailwind, and code Playground

by António Almeida

HTML

<button id="btn" title="Click to show/hide content" type="button" onclick="readmore()">Read More...</button>
<div id="spoiler" style="display:none">spoiler text</div>

JavaScript

function readmore(){
    var btn = document.getElementById('btn');
    var spoiler = document.getElementById('spoiler');
    
    if(spoiler.style.display=='none') {
        spoiler.style.display = '';
        btn.innerHTML = "Read Less ...";
    } else {
        spoiler.style.display = 'none';
        btn.innerHTML = "Read More ...";
    }   
}