[thelist] DIV position in CSS

Is there any sort of hierarchy when it comes to positioning DIV sections in
a style sheet?  Particularly in Netscape?

Do I have to place them in the order in which I structure the DIVs
themselves?  Do they have to go top to bottom, right to left, or anything.
I'm having some trouble with a DIV (only in NS) that refuses to move no
matter where I put the left offset:

#iconDiv {position:absolute; left:445; top:90; width:390; }

(this is my top position command)

TIA

Michael