body {
    margin: 0;
    padding: 0;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 19px;
}
header, footer {
    background-color: black;
    color: white;
}
article {
    background-color: white;
}
section {
    background-color: orange;
}
section:nth-child(2){
    background-color: green;
}