* {
    margin: 0;
    padding: 0;
}

body {
    position: fixed;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    width: 100%;
    height: 100%;
    background: #333;
}

canvas {
    box-sizing: border-box;
    border: solid 1px #000;
    box-shadow: 0 0 10px #000;
}