JSFiddle - React, Tailwind, and code Playground
HTML
<canvas id="canvas" height="1000" width="1000"></canvas>
CSS
#canvas {
height: 100%;
width: 100%
}
JavaScript
var canvas = document.getElementById('canvas');
if (canvas.getContext){
var context = canvas.getContext('2d');
var centerX = canvas.width / 2;
var centerY = canvas.height / 2;
var myRadius = canvas.width / 4;
context.arc(centerX, centerY, myRadius, 0, (Math.PI/180) * 360 , false);
context.fillStyle = 'green';
context.fill()
}