Twenty Eleven – how to add search in nav menu as final list item

How to add search bar to nav menu so that it behaves as though it is next item in the menu rather than independently. Scale browser window very thin, or view on a phone (I view on my iphone) to see issue. I am using a child theme for twenty eleven. The default, when turning off title, places it over the “menu bar”, but as site scales, the search bar behaves independently from the primary menu items. I’ve been researching and implementing various strategies for this for the last month, but nothing i’ve tried seems to work. I’m a complete noob, i am probably missing something obvious.

Ideally the search would just reflow in the menu bar as the last list element in the primary menu as site gets smaller. Even if I set responsive (@media) areas to where it should be at each size, inbetween sizes still have the search not behaving the way I’d like. I’ve also tried adding code into functions file, moving divs around, etc, but same same. It’s currently in default, with slight css mods, while I await brilliance. Can anyone shed some light, please? Thanks!

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