Dogs, Deepak Chopra, Instagram weddings and other signs of change among Iran's middle class

The groom wore a navy blue tuxedo, the bride a custom-made gown with a fish-scale pattern inspired by pictures she found on Instagram.

Waiters passed around French tarts as guests crowded a dance floor pulsating under strobe lights. When the DJ played “Gangnam Style,” a cheer went up from the young...