*{
    box-sizing: border-box
}


header,footer{
    height: 100px;
    border: 5px solid black;
    clear: both;
}

.section1{
    height: 150px;
    border: 5px solid black;
}

.section2 section{
    float: left;
    height: 100px;
    width: 33.3333%;
    border: 5px solid red;

}

.aside1{
    float:right;
    height: 400px;
    width: 20%;
    border: 5px solid blue;

}

.aside2{
    float:right;
    height: 400px;
    width: 20%;
    border: 5px solid blue;

}

.aside3{
    float:right;
    height: 400px;
    width: 40%;
    border: 5px solid blue;

}

.aside4{
    float:right;
    height: 400px;
    width: 20%;
    border: 5px solid blue;

}