* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    background: #111;
    overflow: hidden;
}
canvas {
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: #222;
}