JSFiddle - React, Tailwind, and code Playground

HTML

<button id="mybutt" class="buttonEnabled">
    <span id="myspan">do some work</span>
</button>

JavaScript

butt = document.getElementById("mybutt");
    span = document.getElementById("myspan");   

    butt.onclick = function () {
    span.innerHTML = "doing some work";
    butt.disabled = true;
    butt.className = "buttonDisabled";

    //long running task here

    span.innerHTML = "done";
    };