JSFiddle - React, Tailwind, and code Playground

by Li Sen

HTML

<canvas id="canvas"></canvas>

JavaScript

var canvas = document.querySelector('canvas');
var ctx = canvas.getContext('2d');
var W = canvas.width = window.innerWidth;
var H = canvas.height = window.innerHeight;
  
ctx.fillStyle = '#000';
ctx.fillRect(0, 0, W, H);
ctx.beginPath();
ctx.fillStyle = '#fff';
ctx.arc(W / 2, H / 2, 100, 0, (Math.PI / 180) * 360, false);
ctx.closePath();
ctx.fill();