.container {
    display: grid;
    grid-template-areas:
        "header nav nav"
        "main main main"
        "footer footer footer";
    max-width: 40em;
    margin: auto;
}

.container > header {
    grid-area: header;
    margin-top: 4em;
    margin-bottom: 3em;
}

.container > nav {
    grid-area: nav;
    margin-top: 3em;
}

.container > main {
    grid-area: main;
}

.container > footer {
    grid-area: footer;
    margin-top: 2em;
    margin-bottom: 3em;
}

main img {
    max-width: 100%;
    margin-top: 2em;
    margin-bottom: 3em;
}