.container {
    display:grid;
    grid-template-columns: repeat(1, 1fr);
    grid-template-areas:
        "header"
        "nav"
        "aside"
        "main"
        "footer";
  grid-gap: 5px;
}


@media (min-width: 45em) {
        /* Breite beträgt mindestens 45em */


    .container {
     display:grid;
        grid-template-columns:(3, 1fr);
        grid-template-areas: "header header header"
        "nav nav nav"
        "main main aside"
        "footer footer footer" ;

        }



    nav { grid-area: nav;
    }


header {
grid-area: header;

}

main {grid-area: main;

}

aside {grid-area: aside;

}


footer {grid-area: footer;
}

}