JSFiddle - React, Tailwind, and code Playground

JavaScript

(function(comp){
   var canvas = document.createElement('canvas'),
    ctx = canvas.getContext('2d');

canvas.width = 400;
canvas.height = 200;

document.body.appendChild(canvas);

ctx.beginPath();
var rgr = ctx.createRadialGradient(100, 100, 0, 100, 100, 80);
rgr.addColorStop(0, 'rgba(0,0,0,1)');
rgr.addColorStop(1, 'rgba(0,0,0,0)');

ctx.fillStyle = rgr;
ctx.fillRect(20, 20, 110, 160);


var rgr = ctx.createRadialGradient(160, 100, 0, 160, 100, 80);
rgr.addColorStop(0, 'rgba(0,0,0,1)');
rgr.addColorStop(1, 'rgba(0,0,0,0)');

ctx.beginPath();
ctx.fillStyle = rgr;
ctx.fillRect(130, 20, 160, 160);
})();