body {
    background-color: black;
    margin: 0;
}

div.introduction {
    position: fixed;
    color: white;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    font-size: xx-large;
}

div.introduction .button {
    font-size: 2em; /* Adjust the value as needed */
}