Well, despite thinking I’d first searched the forum for the answer before posting it, I eventually realized that the one post I’d overlooked was the most recent one, by Cidneym (@cidneym), who brought up the same thing about the pink background on the mobile menu.
I’ve since replaced my CSS with Cidneym’s (thank you!), changing only the nav background color. I’m delighted that this fixed my Hover issue. However, the pink background on the main menu remains when any page is loaded, but disappears after the menu is clicked.
Help?