Sure, it’s still in progress, but it’s: http://hull1.com/bert
The display:none was working fine, though.
Hm, when I try that code, it shows two copies of the menu on the screen when I start scrolling down. It seems like the original menu is still there and a second menu appears as you scroll down.
I had the same question, and this is how I did it. I made a child theme containing this css:
@media (max-width: 680px) {
.site-navigation.main-navigation.use-sticky-menu.sticky {display:none;}
}
If anyone has a better solution, I’d be curious to know, but it seems to work well.