Shirt color with light grey suit for really blond guy

I am a groomsman in a wedding where the couple is taking a very hands-off approach to how the wedding party should dress. It is an outdoor wedding at a beach camp at the Gulf of Mexico that the couple is trying to keep fairly casual. I was asked wear any light grey suit, and no tie. I have a very well-fitting slim cut light grey suit. But I am very blonde and have a very light Scandinavian type complexion, so since I am not supposed to wear a tie I think that I should be very careful to match the color and style of the dress shirt. I don’t want to disappear into the sandy background, but a really bright color seems too attention-desperate. In a nutshell: Without being able to spice things up with a tie, what color family of dress shirt would look nice on a Scandinavian type complexion in a light grey suit?