beveled lines

I'm trying to create background lines like is in this site.
http://www.pixelbrick.com/

If you look where it is blue and there is the 4 cubes beside the pixelbrick logo the background blue has strokes or lines that looked beveled out of the solid blue can anyone tell me how to do this.

Thanks.

I recommend drawing the lines yourself and using the dodge/burn tool to make them appear beveled.

Exactimundo. Whip out your airbrush tool and start drawing. Play around with blending modes and opacities to get it where you want it. It'll take some time to get it right though.