* { margin: 0; padding: 0; box-sizing: border-box; }
html, body {
    width: 100%;
    height: 100%;
}
body {
    background: #1a1a2e;
    overflow: hidden;
    touch-action: none;
    user-select: none;
    -webkit-user-select: none;
}
canvas {
    display: block;
    position: fixed;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    height: 100vh;
    width: auto;
    max-width: 100vw;
}