It should be pink and slightly cloudy, not completely clear. Use pure cranberry juice instead of “cranberry juice cocktail”—which is really more like an apple juice with cranberries added to it, rather than straight cranberry juice. If you are not used to real cranberry juice, you may be pleasantly surprised—or you may completely hate it. Real cranberry juice is often sold in glass jars and requires shaking before you pour.
Experiment with the amount of cranberry juice, lime juice, and triple sec to adjust taste. The triple sec is sweet and offsets the tartness of the cranberry juice and lime juice. I prefer a more tart version, so I use more lime juice.
as an aside, I do like a good cosmo, but it's not technically a cocktail anyway.
A review of The Europeans: Three Lives and the Making of a Cosmopolitan Culture by Orlando Figes
Plus, the whole sweet cocktail thing was a more modern invention of the prohibition era to cover up the taste of harsh spirits. Plenty of older cocktails around.
EDIT: It kinda feels like the rule about email address parsing. The only good rule is that it has an @ symbol.