I'm looking for a way to add or change a property value in a previously defined CSS class - not just HTML objects that have that class.  Then if later objects are assigned with this class, the objects would inherit the properties of the updated class.  For example, if I change the class "image" to add "display:none", and then add the "image" class to an object, it would be displayed or not displayed depending on how this was previously defined.  Thanks.