Codecademy Sample Solution: Codeyear Marginally different

/* sample solution to style.css */
div {
    width:100px;
    height:100px;
    border:3px solid #444;
    padding:4px;
}

#box1 {
    background:#f00;
    float: left;
}

#box2 {
    background:#0f0;
    float: left;
    margin-left: 20px;
}