Responsive Custom Menu in admin-bar

I am using the twenty thirteen theme and I want to add a custom menu to it. That is easily done using add_menu etc, but when viewed on a small screen the custom menu disappears. Is it possible to make it responsive similar to the default menu items?

I have tried a number of admin bar plugins to achieve the above with the without results.

Or is this impossible
Regards,

Nothing is impossible, just ridiculously difficult and expensive!