@media only screen and (min-width: 800px) {  
    #primary_nav_wrap ul ul {
            background-image: linear-gradient(#5CB7B9, #8CB0DF);
        }
}
@media only screen and (max-width: 800px) {
    .header .header__links {
        background-image: linear-gradient(#5CB7B9, #8CB0DF);
    }
    #primary_nav_wrap ul ul {
        background-image: linear-gradient(#5CB7B9, #8CB0DF);
    }
}