Short Code: Can I make a var conditional?

My question is. Is there a way to make a var conditonal?

For example. I would like a cutomer to be able to do the following.

Pick the Style of the product:
var1[Pen Style|Style 1|Style 2|Style 3]
If Style 1 or 2 is picked then:
var2[Nib Size|Fine|Extra Fine]:var3[Color|Pink|Beige|Green|Blue]

If Style 3 is picked then: var2 and var 3 is not shown, only var4 is shown
var4[Color|Silver-white|Yellow-gold|Pink|Purple|Blue|Brown|Black]

Any ideas how to do this?

Also, any way to allow a cutomer to choose a QTY at the Product Page level before adding to the cart?

The page I need help with: [log in to see the link]