JSFiddle - React, Tailwind, and code Playground

HTML

<div id="btcode">boton</div>
<div class="code1"></div>
<div class="code1"></div>

CSS

.code1 {
    width:200px;
    height:200px;
    background-color:#333;
    margin:2px;
}

#btcode {
    cursor:pointer;
}

JavaScript

var code = document.getElementsByClassName("code1");
btcode = document.getElementById("btcode");

btcode.addEventListener("click", function () {
code.style.width = code.style.width == "100px" ? "200px" : "100px";}, false);;