*{
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
}
html, body
{
    height: 100%;
    margin: 0;
    padding: 0;
    background-color: #333;
    /* background-color: rgba(194, 199, 202,1); */
    overflow: hidden;
}
canvas
{
    background-color: rgba(194, 199, 202,1);
    /* border: 1px solid black; */
    width:   100%;
    height:  100%;
    display: block;
}