JSFiddle - React, Tailwind, and code Playground

HTML

<div id="chart" style="position:relative; width: 100%; float:left; height: 220px;"></div>

CSS

#chart
{
 
 background: green;   
}

JavaScript

window.onload=function(){
    var elem = document.getElementById('chart');
    elem.style.width = 70 + "%";

}