Selena Gomez will forever be a style icon in our eyes. Although she’s recently taken a back seat from performing sell-out shows, her wardrobe is clearly still filled with killer ensembles.  The Rare Beauty founder posted a seriously adorable Instagram series to her 428 million followers yesterday to congratulate her musical maven boyfriend Benny Blanco on his new cookbook Open Wide: A Cookbook for Friends. Although the celebration was all about her beau, we take our eyes off the Love On singer’s 1950s-inspired mini dress.  MORE: Selena Gomez just unveiled a game-changing makeup must-have RELATED: Selena Gomez’s stunning dress gives Meghan Markle’s favourite style a cool-girl makeover © Instagram / @selenagomezIt doesn’t get cuter than this The Disney actress’ celebratory ensemble consisted of a bustier black and white halter neck polka dot mini dress with accenting silver buttons, a pair of sheer black tights and simple gold hoop earrings.  She paired her cutesy dress with a middle-parted, slicked-back low bun and a glowing face of what we can only assume is Rare Beauty products.  © Instagram …