Problem with Responsive Theme Vantage

HI,

I reallty appreciate the vantage theme but since I’m the beginner I can not handle the responsive layout.
In the standard theme there is an option “responsive layout” but it does not work.
Whenever I want to reduce the screen on site it makes a big mess in laout, not even mention about the mobile devices. Is there any simple alternative for me to change the code in the existed site or should I extend it to the pro version?

I would be grateful for any help !
please see my site www.stalcomplex.pl

URL: http://www.stalcomplex.pl