This talks aims to showcase some examples of CSS structures that are able to respond to user interactions like scroll, click on an element or filling a form. By taking advantage of some recently introduced pseudo selectors like :target, :valid, :required and :checked we can develop a whole new range of CSS rules that can react while the user interact with the page. During the talk we’ll explore some of these rules and how we can replace some well known javascript powered widgets with their pure CSS counterparts