:root {
    --background-color: #F2F2F7;
}

@media (prefers-color-scheme: dark) {
     :root {
        --background-color: #000000;
    }
}

body {
    background-color: var(--background-color);
}


.center {
    margin: 0;
    position: absolute;
    top: 50%;
    left: 50%;
    margin-right: -50%;
    transform: translate(-50%, -50%)
}