I have a problem with black/white. Look at the right side, where black menu panel meets shadow. The shadow has less contrast and panel appears 1px smaller...
Who can tell me how to improve this and who can refer to some articles to read about this illusion?

looks to me like you have a 1px border on the right hand side and the bar is shy 1px.

but i could be wrong.

hardly noticeable realy.
If it wasnt pointed out I dont think you would see it

yes , i think it is not a big problem, you visitors could'n notice that

I also agree. I don't really see a problem with it. Very very minor.

Skinny

ok. Then no problem I just thought that everyone can see it
But i would be glad to get any reference to article about this effect.

optical illusion.

like;

http://www.michaelbach.de/ot/lum_herGrid/index.html
or
http://www.michaelbach.de/ot/mot_eyeJitter/index.html

Okey... its not so big probs its a minor problem.
Dont worry about that...

I think that's not a big problem.. That is ok dude..