*{
    margin: 5px;
    padding: 0px;
    text-align: center;
}
html, body{
    width: 100%;
    height: 100%;
}

header{
    border: 1px solid red;
    color:red;
    height: 15%;
    width: 98%;
}
aside{
    margin-top: 10px;
    height: 30%;
    width: 39%;
    border: 1px solid green;
    color: green;
    float:left;
}
article{
    margin-top: 10px;
    margin-bottom: 10px;
    height: 70%;
    width: 58%;
    border: 1px solid yellow;
    color: yellow;
    float:left;
}
footer{
    border: 1px solid black;
    height: 10%;
    width: 98%;
    clear: both;
}