body {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
}

#center {
    width: 80%;
    max-width: 1200px;
    margin: auto;
    flex: 1;
}

footer {
    width: 100%;
    text-align: center;
    margin-top: auto;
}

canvas {
    width: 100% !important;
    height: auto !important;
}