A simple mechanism for adding style
CSS is a style sheet language that can describe the presentation of a document written in a markup language. It is used to create beautiful user interfaces/webpages, and with the latest CSS versions, UI elements’ transitions too. It can be applied to any XML document (think plain XML, SVG, and XUL), although it is usually utilized to set the visual style of web pages and user interfaces in HTML AND XHTML. CSS can be used for rendering in speech and on other media.