430Calvin Klein Collection wardrobe for Lupita Nyong’o, Emma Watson, Margot Robbie was all about sustainability. Other stars who wore the brand at the red carpet included Michael B. Jordan, Common, Amandla Stenberg, Nate Parker, Jonathan Groff, Diplo, Odell Beckham Jr., Adwoa Aboah, Luka Sabbat and Vogue’s Camilla Nickerson for their appearances at the 2016 Costume Institute Benefit at the Metropolitan Museum of Art in New York City.

With the event’s theme as “Fashion in an Age of Technology,” and Watson rocked the red carpet with her stunning gown created using sustainable products.The gown combined “creativity, technology, and fashion” to send a bold message about curbing waste, she wrote on facebook. According to Watson, the fabrics of the dress were woven from recycled plastic bottles — “one of the biggest pollutants on the planet,” she noted. The cotton used in the design was organic — not the conventional kind that uses chemicals to grow and thus damages the earth and puts workers’ health at stake. Even the zippers were crafted from recycled materials.

Along Watson and Lupita Nyong’o, Margot Robbie joined the duo in celebrating Eco-Age’s #GreenCarpetChallenge.