body {
    margin: 0;
    height: 100%;
}

canvas {
    position: absolute;
    top: 0;
    left: 0;
    background-image: linear-gradient(bottom, rgb(105, 173, 212) 0%, rgb(23, 82, 145) 84%);
    background-image: -o-linear-gradient(bottom, rgb(105, 173, 212) 0%, rgb(23, 82, 145) 84%);
    background-image: -moz-linear-gradient(bottom, rgb(105, 173, 212) 0%, rgb(23, 82, 145) 84%);
    background-image: -webkit-linear-gradient(bottom, rgb(105, 173, 212) 0%, rgb(23, 82, 145) 84%);
    background-image: -ms-linear-gradient(bottom, rgb(105, 173, 212) 0%, rgb(23, 82, 145) 84%);

    background-image: -webkit-gradient(linear, left bottom, left top, color-stop(0, rgb(105, 173, 212)), color-stop(0.84, rgb(23, 82, 145)));
}