header nav ul {
    list-style: none;
}
header nav {
    background-color: aqua;
    background-image: url('../images/pancake-menu.svg');
    background-repeat: no-repeat;
    height: 40px;
}
header nav.collapsed ul {
    display: none;
}





@media screen and (min-width: 40em) {
    header nav ul,
    header nav.collapsed ul { 
        display: flex;
        
        
    }
    header nav ul li {
        flex-basis: 17%;
    }    
}