.header{
    background: #f9f9f9;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-left: 2rem;
    padding-right: 2rem;
}

/* qnd a tela for maior que 0, ele aplica esses estilos */
@media screen and (min-width: 0) {
    .header {
        justify-content: center;
        padding: 0 1rem;
    }
}

/* qnd for menos, ele aplica os estilos */
@media screen and (min-width: 768px) {
    .header {
        justify-content: space-between;
        padding: 0 5rem;
    }
}