body {
    background-color: azure;
    font-family: Arial, Helvetica, sans-serif;
    margin: 0px;
    padding: 10px;
}

main {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    grid-template-areas: 'arriba arriba arriba' 'menu menu menu' 'contenido contenido menu2' 'publi1 publi2 menu2' 'pie pie pie';
    grid-gap: 10px;
    min-height: 100vh;
}

header {
    background-color: cornflowerblue;
    color: white;
    grid-area: arriba;
}

#menu_arriba {
    background-color: salmon;
    color: white;
    grid-area: menu;
}


/* #menu_arriba ul {
    display: flex;
}

#menu_arriba ul li {
    list-style: none;
    margin: 15px;
} */

section {
    grid-area: contenido;
    background-color: seashell;
    padding: 10px;
}

#menu_lateral {
    background-color: rgb(255, 194, 187);
    color: black;
    grid-area: menu2;
}

.publi1 {
    background-color: blueviolet;
    border-radius: 6px;
    height: 100px;
    grid-area: publi1;
}

.publi2 {
    background-color: blueviolet;
    border-radius: 6px;
    height: 100px;
    grid-area: publi2;
}

footer {
    background-color: black;
    color: white;
    grid-area: pie;
    height: 150px;
}

@media screen and (max-width: 640px) {
    main {
        grid-template-columns: 1fr 1fr;
        grid-template-areas: 'pie pie' 'arriba arriba' 'menu menu2' 'contenido contenido' 'publi1 publi2';
    }
}