What’s black and white and on your computer? If it’s not Sioux City native Gateway Computing, it may be against the law. It began with a bright idea for “Stretch Pets,” elastic bands holding plush animal heads designed to adorn a computer monitor. Colorado-based Companion Products went to Gateway to see if the company wanted to buy one of the designs, dubbed Cody Cow. Of the bear, cat, moose, monkey, penguins and more, it was the most popular Stretch Pet. Gateway declined, but the company had trademarked its black-and-white-spotted logo a dozen years ago, and after finding the product on the market sued the makers of Cody Cow. The toymaker appealed, citing Ben and Jerry’s ice cream and other black-and-white labeled products. But this week the eighth U.S. Circuit Court of Appeals agreed that these days the spots mean Gateway, and Cody Cow is unfair use.