* { margin: 0; padding: 0; box-sizing: border-box; }
html, body {
    width: 100%;
    height: 100%;
    background: #000;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}
canvas {
    image-rendering: pixelated;
    image-rendering: crisp-edges;
    max-width: 100%;
    max-height: 100%;
}