#main-container {
    width: 100%;
    margin: auto;
    color: black;
}

#game-canvas {
    width: 100%;
    margin-top: 1em;
    margin-bottom: 1em;
    padding-left: 0;
    padding-right: 0;
    margin-left: auto;
    margin-right: auto;
    display: block;
}

#game-canvas {
    border: 0.2em solid black;
}

@media only screen and (min-width: 40em) {
    #main-container {
        width: 80%;
    }
    #game-canvas {
        width: 90%;
    }
}

@media only screen and (min-width: 48em) {
    #main-container {768pxn
        width: 70%;
    }
    #game-canvas {
        width: 80%
    }
}

@media only screen and (min-width: 62em) {
    #main-container {
        width: 70%;
    }
    #game-canvas {
        width: 70%;
    }
}

@media only screen and (min-width: 75em) {
    #main-container {
        width: 50%;
    }
    #game-canvas {
        width: 60%;
    }
}