Add Border to Menu – Please Help

Hello all,

My menu bar is white with black/grey buttons and the background of the sheet beneath it is primarily white, with a semi-translucent black pattern – I’d like a 1px thick black border separating the menu and sheet just so that the pattern doesn’t flow into the white of the menu bar – it’s somewhat jarring to my eye. Any idea how I can get a 1px black border inbetween the sheet and the menu? I ONLY want the line there, not between the menu and the header, as well.

I’m not sure of what CSS code to use, or where to put it.

Thanks,