Unity WebGL 16:9 responsive canvas - you can change the ratio by changing css padding

unity16.9.css

/* The style: */ 

#game:before {
    display: block;
    content: " ";
    width: 100%;
    padding-top: 56.25%;
}

#game {
    width: 60%;
}

#game > canvas {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
}

/* this is applied to the canvas where the unity game is spawned: <div id="game"></div> - var gameInstance = UnityLoader.instantiate("game", "Build/v 0.3.0.json");*/