JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.1/phaser.js"></script>

CSS

html, body {
  margin: 0;
	padding: 0;
	background-color: red;  
}

JavaScript

var game = new Phaser.Game(window.innerWidth, window.innerHeight, Phaser.CANVAS, null, { create: create });

function create() {
    game.stage.backgroundColor = "#0000FF"; // blue
}