Victoria Beckham has mastered the art of understated fashion, and her vacation dress style is proof that the simplest outfits can also be some of the most flattering. With a sleek silhouette, rich neutral color and easy fit, it’s the kind of comfy maxi dress women over 50 reach for again and again. Beckham was spotted in Saint-Tropez wearing a chocolate brown spaghetti-strap maxi dress that skimmed her figure in all the right places. She styled …