* {
    font-family: sans-serif;
}
#center {
    position: fixed;
    top: 50vh;
    left: 50vw;
    transform: translate(-50%, -50%);
    text-align: center;
}
img {
    max-width: 50vw;
}
a {
    color: white;
    text-decoration: none;
    padding: .5em;
    margin: .5em;
    font-size: x-large;
    background: red;
    border-radius: .5em;
}