The concept of web design used to be simple - designers would develop content for a popular desktop screen, using a layout which works for most devices to produce well laidout and cohesive pages. (Quelle: Responsive Web Design with HTML5 and CSS3 Essentials, Libby et al., Packt Publishing 2016, ISBN: 978-1-78355-307-5, Chapter 1 Introducing RWD, Seite 6 ff.)