Center facebook like button on menu top bar

So my website is Due fili d’erba and I’m trying to put a facebook like button on the menu top bar. If I would add the code on the header it would show fine on the computer version, but on the mobile version the button wouldn’t be aligned.. So I thought I might add a div and try to put some margins or a vertical center but nothing: when I put the div the button would go even more out of place. Any ideas?

Thank you very much in advance