An apparel designer analyzed the pants Lululemon accused Costco of copying — and sided with the warehouse club

A customer shops at a Lululemon store in Florida. Joe Raedle/Getty Images Lululemon sued Costco, accusing it of selling apparel that appears to copy the athleisure brand's designs. Joe Ng, CEO of fashion studio Shift, compared pants from the two companies in a YouTube video. Ng said the Costco…