Because the name of a page element or widget does not go into the HTML, there is no way to style one element without affecting all other elements of the same type. Imagine that one group box needs to display elements with a larger font, you would have to style all individual elements in the group box. To avoid that, I created a little widget, CssSelectorWidget,that allows the developer to get hold of an element and style it or all elements within it. The widget documentation has examples and screenshots of the designer and the results.