ul {
    list-style-type: none;
    background-color: #111;
    overflow: hidden;
    margin: 0;
    padding: 0;
}
li {
    float: left;
}
a {
    display: block;
    background-color: #333;
    margin: 3px;
    padding: 20px 30px;
    text-decoration: none;
    color: white;
}