.game-container {
    position: relative;
    width: 100%;
}

.game-container-16-9 {
    padding-bottom: 56.25%;
}

.game-container-4-3 {
    padding-bottom: 75%;
}

.game-container canvas {
    position: absolute;
    width: 100%;
    height: 100%;
    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
}