JSFiddle - React, Tailwind, and code Playground

HTML

<canvas id="can" style="width:100%;height:100%;"></canvas>

JavaScript

var canvas = document.getElementById("can");
var ctx = canvas.getContext("2d");
var fun = function () {
    ctx.canvas.width = ctx.canvas.width;
    var today = new Date();
    var target = new Date("10-28-2016");
    var diff = new Date(target - today);
    var str = diff.getMonth() + ":" + diff.getDate() + " " + diff.getHours() + ":" + diff.getMinutes() + ":" + diff.getSeconds() + ":" + diff.getMilliseconds();
    ctx.font = "bold 32px Arial";
    ctx.fillText(str, 10, 30);
    ctx.fill();
};
setInterval(fun, 10);