In addition to being a popular buzzword in website design today, responsive design is focused on creating websites that respond to the myriad devices and environments from which we access the Internet in our rapidly-changing world. CSS3 is an important part of successful responsive design. Using fluid layouts, media queries, scalable images, and creative content display, you can achieve a mobile-up responsive design that will serve content to your users on whatever device they happen to be using. In this module, we explore the techniques and concepts needed to target styles to improve user experience regardless of platform.