"behind the Orange curtain" is the sometimes derogatory, sometimes light-hearted term used to describe Orange County, California, especially as seen from bordering Los Angeles County.
Residents of Orange County are more suburban than their big-city neighbors, but it could be argued the former are more classic yuppies.
The Orange Curtain is (of course) virtual - it doesn't exist in physical space.
The term is an (obvious?) comparison to the other virtual curtains in the world: The Iron Curtain (communist versus capitalist); the Bamboo Curtain, etc.
