body {
    color: #fff;
    opacity: 0.87;
    background-color: #000a12;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
}

#clock {
    font-family: Roboto, sans-serif;
    font-size: 4em;
    color: #fff;
    opacity: 0.87;
    text-shadow: 1px 1px #000;
}