Easily Implement 2x Retina Background Images Using SCSS

Here’s the problem. You have a background image somewhere on your website that looks great on your trusty, old-fashioned desktop PC monitor, but appears blurry or pixelated on your Retina display iPad. You can use CSS media queries to target high-density displays and supply them with a separate, 2x resolution version of your image, but with this simple SCSS mixin, the entire process becomes downright easy.