Responsive CSS is a class to handle pages html5, jQuery, CssResponsive, CssBrowser, CssVersion. Class is designed to load the appropriate CSS styles depending on the browser like Mozilla, IE, etc. Class also recognize the screen resolution, thus adapting to a device such as tablet, phone, etc. By reading the right style for your device. Identifies the version of the style supported by your browser. All this results in a significant acceleration loading, because they are charged only the styles that are just at the time needed. In the classroom you will find a few other things you need to use a web page that may help facilitate the work. Check javascript, cookiesmedia etc. Class will prepare more efficiently css responsieive for devices and for our applications.