body {
    margin: 0px;
    font-size: 16px;
}

header {
    background: lightyellow;
    padding: 20px;
}

.logo {
    width: 64px;
}

.content {
    background: #333;
    color: #fff;
    padding: 20px;
}

footer {
    background: grey;
    color: white;
    padding: 20px;
}