My website (twenty eleven) shows an ugly grey border around the header and menu. I spend a few hours trying all the tips and tricks I can find about this subject. But nothing worked. I tried all the changing of codes I was offered trough google, but I cannot even find the codes in style.css. As if I have a different version or something, (which is not the case). I set almost every border and padding I could find on 0px, or 'none', but my website seems to stay completely unaffected. I'm probably doing something really stupid.
Can somebody assist me?