html,body {
    width: 100%;
    height: 100%;
    margin: 0;
    text-align: center;
    padding: 2em;
    overflow: hidden;
    -webkit-touch-callout:none;
    -webkit-user-select:none;
    -khtml-user-select:none;
    -moz-user-select:none;
    -ms-user-select:none;
    user-select:none;
    -webkit-tap-highlight-color:rgba(0,0,0,0);
    padding: 0;
    margin: 0;
    background: rgb(17,10,40);
    background: linear-gradient(180deg, rgba(17,10,40,1) 0%, rgba(57,60,142,1) 75%);
}
canvas {
    display: block;
    box-shadow: 0 0px 8px 0 rgba(0, 0, 0, 1);
    max-width: 100%;
    max-height: 100%;
    position: absolute;
    margin:auto;
    top:0;
    bottom:0;
    left:0;
    right:0;
}