body{
    margin: 0px;    
    text-align: center;
}

header{
    margin: 0.5%;
    width: auto;
    height: 10%;
    color: red;
    border: 1px solid; 
}

aside {
    margin: 0.5%;
    width: 30%;
    height: 30%;
    float: left;
    color: green;
    border: 1px solid; 
}

article{
    margin: 0.5%;
    float: left;
    width: 67.5%;
    height: 75%;
    color: yellow;
    border: 1px solid; 
}

footer{
    margin: 0.5%;
    width: 100%;
    height: 10%;
    float: left;
    color: black;
    border: 1px solid;
}