JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://www.chartjs.org/assets/Chart.js"></script>
<div id="one">
    <canvas id="myChart1" width="400" height="400"></canvas>
</div>
<div id="two" class="hidden">
    <canvas id="myChart2" width="400" height="400"></canvas>
</div>
<button type="button" class="btn" onClick="swap()">Swap!</button>
<div id="info"></div>

CSS

.hidden {
    display: none;
}

JavaScript

var data1 = {
    labels: ["January", "February", "March", "April", "May", "June", "July"],
    datasets: [
        {
            label: "My First dataset",
            fillColor: "rgba(220,220,220,0.2)",
            strokeColor: "rgba(220,220,220,1)",
            pointColor: "rgba(220,220,220,1)",
            pointStrokeColor: "#fff",
            pointHighlightFill: "#fff",
            pointHighlightStroke: "rgba(220,220,220,1)",
            data: [65, 59, 80, 81, 56, 55, 40]
        }]
};
var data2 = {
    labels: ["January", "February", "March", "April", "May", "June", "July"],
    datasets: [
        {
            label: "My First dataset",
            fillColor: "#FD6260",
            strokeColor: "#FD6260",
            pointColor: "#FD6260",
            pointStrokeColor: "#fff",
            pointHighlightFill: "#fff",
            pointHighlightStroke: "rgba(220,220,220,1)",
            data: [65, 59, 80, 81, 56, 55, 40]
        }]
};

var options = {
    scaleShowGridLines : false,
    scaleShowHorizontalLines: false,
    scaleShowVerticalLines: false,
 }

var cxt = document.getElementById("myChart1").getContext("2d");
var chart = new Chart(cxt).Bar(data1,options);

var cxt2 = document.getElementById("myChart2").getContext("2d");
var chart2 = new Chart(cxt2).Bar(data2,options);
        
swap= function() {
     console.log(document.getElementById("one").className);
     document.getElementById("one").className = "hidden";
     document.getElementById("two").className = '';
    console.log(document.getElementById("one").className);
}