When bleach hits blue it usually turns a bright orange. You don't want orange shorts. You can get this stuff called "Rit dye remover" and lighten your shorts that way. Its a powder that you boil on the stove and you add your shorts and stir for about 20 to 45 minutes. I did this to lighten a pair of jeans and it worked wonders! You can get it in almost any laundry aisle.