JSFiddle - React, Tailwind, and code Playground

HTML

<div class="source">s1</div>
<div class="source">s2</div>
<div class="source">s3</div>
<input type="button" onclick="toggle('source')" name="toggle_button" value="toggle" />

CSS

.source { display:none }

JavaScript

function toggle('source'){

    var divs = document.getElementsByClassName('source');
    for(var i=0; i<divs.length; i++) { 
          divs[i].style.display='';
          
    
    } 
}