html {
    background-color: black;
    color: white;
    font-family: arial;
    font-size: 15px;
    margin: auto;
    max-width: 900px;
    text-align: center;
}

h1 {
    font-size: 30px;
    text-align: center;
}

h2 {
    font-size: 20px;
}