There's a sense of unease and tension throughout the movie that's classic Petzold, and the gorgeous photography goes very well with it. Unfortunately I think that the sophisticated backdrop is turned down by a silly teen love story. Petzold knows better.
Minor, of course, coming from Petzold, but there are brief moments of unease which could have been coaxed into full-on dread to imbue the shrewdly if not always gorgeously lensed German vistas (expect no less from Petzold's constant helpmeet/co-auteur, Hams Fromm). Other hallmarks are still in order : "non-spaces", impetuous and laconic characters, seamless montage, narrative misdirection. Revel.
"A love story transcending boundaries, without a future." - quite true!
Is there a particular reason behind Ana's tumbling Bosnian? I might be reading too much into what could simply be some code-switching gone awry, but those odd sentences had me confused throughout the film.