JSFiddle - React, Tailwind, and code Playground

HTML

<span id="p1">
<div class="button"><a href="javascript:void()"     onclick="ChangeStyle();alert('hello');">CONFIRM  </a></div></a>
</span>

CSS

.button { padding: 20px; }
.next { border: 2px solid red; }
.move { background-color: #ccc; }

JavaScript

function ChangeStyle()
{
    var div = document.getElementById('p1').getElementsByTagName('div')[0];
    div.className = 'button next move';
}