Mobile menu – some entrys disabled

Hi, I'm using the Catch Box Theme with my personal child theme. I would update to the actual version. But I have a problem. I added a CSS class in the menu (no-mobile-menu-item) In the CSS I added: .no-mobile-menu-item {display:none;} In the normal desktop menu the links are not shown (correctly) if I add .no-mobile-menu-item {display:none;} for the desktop version. But in the responsive menu they are shown. I don't know why. I should not be shown (display:none). I just tested this offline. So, I can't send you link to show. Perhaps it is also possible to create a second menu, just for mobile view. I would be happy if you could give me hints to solve my problem. Best Regards, mailhunter