A system and method of controlling user interface features of a web application is provided. The system comprises a collection of user interface control elements, a collection of skin templates comprising extensible markup language based markup contained as children of a container element, and a collection of control element instructions for performing actions associated with the control elements. Each control element comprises a namespace, common attributes for defining graphical features of the control element and for associating the control element with the internal state of the core control element, other attributes for defining attributes that affect the intrinsic behavior of the control, and a skin template reference attribute for referencing a skin template. Each instruction is associated with a control element.