a {
    text-decoration: none;
    display: inline-block;
    padding: 8px 16px;
}

a:hover {
    background-color: #ddd;
    color: black;
}

.previous {
    background-color: #cccccc;
    color: black;
}

.next {
    background-color: #444444;
    color: white;
}

.round {
    border-radius: 75%;
}