body{
    font-family: Arial, Helvetica, sans-serif;
}
header{
    background-color: red;
    grid-area: header;
    height: 70px;
}
aside{
    grid-area: aside;
    background-color: yellow;
    width: 200px;
}
aside div{
    background-color: white;
    border: 1px solid red;
    width: 80%;
    height: 50px;
    margin-left: auto;
    margin-right: auto;
    margin-bottom: 5px;
}

aside div h3, p{
    text-align: center;
    margin-top: -3px;
}

section{
    grid-area: section;
    background-color: greenyellow;
    width: 200px;
}

article section{
    width: 100%;
    background-color: white;
}

nav{
    display: flex;
    justify-content: top;
    flex-wrap: wrap;
    flex-direction: column;
    margin-left: auto;
    margin-right: auto;
    margin-top: 10px;
    border: 2px solid black;
    background-color: white;
    height: 150px;
    width: 80%;
    text-indent: 20px;
}

nav h2{
    font-size: medium;
}

footer{
    background-color: gray;
    grid-area: footer;
    height: 50px;
    text-align: center;
}

.article{
    grid-area: article;
}

img{
    border: 2px solid black;
}

.container{
    width: 800px;
    margin-left: auto;
    margin-right: auto;
    display: grid;
    grid-template-columns: auto auto auto;
    grid-template-areas: 'header header aside'
    'section article aside'
    'section article aside'
    'section article aside'
    'section article aside'
    'footer footer footer';
}