SOURCE

header,
footer,
footer a {
    background-color: #000;
    color: #ffffff;
    text-align: center;
    text-decoration: none;
    padding: 5px 0;
}

.wrapper {
    width: 500px;
    margin: 0 auto;
    background-color: lightgrey;
}

.content {
    padding: 0 1em;
}