The week's best celebrity style: Gwen Stefani, Elle Fanning, Marion Cotillard and more

Marion Cotillard hit the London premiere of ‘Two Days, One Night’ in an off-the-shoulder Christian Dior creation with floral embellishments and suede Dior heels with metallic accents. (Photo: © Getty)

Kate Mara looked effortlessly chic on the streets of Manhattan wearing a tweed crop top by Sea, Zara jeans, stacked H&M heels and a Coach bag. (Photo: © Getty)

Elle Fanning proved she’s a master of a high fashion in a corseted frock from Vivienne Westwood’s Gold Label that featured an exaggerated sweetheart neckline and bold pattern. She perfectly accented the dress with sparkling rose-gold Christian Louboutin pumps. (Photo: © Getty)

Out and about in Beverly Hills, newly married Naya Rivera Dorsey took her cue from Old Hollywood in a little white dress from Rebecca Minkoff, Hermes ‘Kelly’ bag and rose-printed Stuart Weitzman pumps. (Photo: © Getty)

‘New Girl’ star Hannah Simone attended the L.A. screening of ‘Let’s Be Cops’ in a cropped two-piece ensemble by RVN and super sexy Giuseppe Zanotti heels. (Photo: © Getty)

‘America’s Got Talent’ judge Melanie Brown attended the reality show’s red carpet event at New York’s Radio City Music Hall in a little Gucci dress wonderfully reminiscent of her Spice Girls days. (Photo: © Getty)

Olga Kurylenko stunned at the L.A. premiere of ‘The November Man’ in a wool pencil dress by Michael van der Ham that shone with crystal embellishments, and completed her look with vintage ankle-strap heels and oversized diamond earrings. (Photo: © Getty)

Quintessential cool-girl Gwen Stefani donned a striped sweater, DSquared2 boyfriend jeans, GX by Gwen Stefani ‘Haru’ sandals and a metallic crinkled clutch for a walk through L.A. (Photo: © Getty)