html {
    background-color: springgreen;
    color: blue;
    text-align: center;
    font-size: 20px;
    font-style: italic;
}
html, body {
    height: 100%;
    margin: 0;
}
body {
    display: flex;
    flex-direction: column;
    justify-content: center;
}
h1 {
    line-height: 1;
}
h1, p, footer {
    margin: 0.5rem;
}
h4 {
    margin: 0;
}
.year {
    font-size: 0.8em;
}