body, html {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow:auto;
}
canvas {
    padding-left: 0;
    padding-right: 0;
    margin-left: auto;
    margin-right: auto;
    margin-top: 0px;;
    margin-bottom: 0px;;
    display: block;
}