Building shelves

I am completely and totally unhandy, so I asked my husband to help me out with my fabric storage problem. For the faithful reader you might remember me complaining about piles and piles of messiness.Thankfully he said yes, so the last couple of weeks he has been down in the cold and dusty kelder ( poor thing ) building some shelves. Considering he never make anything except the times I am asking him, I am very happy about the result ! Before sanding and painting I want to add something that might help an ordinary shelf look more pretty, a crown molding. 

Photos © Aina - Modern Country
A: Attach the crown molding perfectly against the top plate ? B: Or a few millimeter above the edge ?
Personally I think It looks prettier to attach the molding a few millimeter above the edge of the top plate, but maybe I have stared myself blind. I think I need your help, what do you think looks more beautiful ? Or is it a right or wrong way to do it ?? I would be happy to hear your opinion !
~ Aina ~