JSFiddle - React, Tailwind, and code Playground
by Tinclon
HTML
<canvas id="canvas"></canvas>
CSS
#canvas {
background-color: lightgrey;
}
JavaScript
var boxSize = 600;
var lineWidth = 3;
document.getElementById('canvas').setAttribute('width', (boxSize + lineWidth));
document.getElementById('canvas').setAttribute('height', (boxSize + lineWidth));
context = document.getElementById('canvas').getContext("2d");
for(var i = 0 ; i <= 20 ; i++) {
context.fillRect(0, i * (boxSize / 20), boxSize + lineWidth, lineWidth);
context.fillRect(i * (boxSize / 20), 0, lineWidth, boxSize + lineWidth);
}