UML modeling of a "Conception and creation services" project

I have a class called "creations" , defining all the creations offered by the company, e.g., Flashes, websites, logos, brochures, etc.

So this class will have a child class, whose name is "creations_category", which defines the categories contained within the "creations" class.

This child class contains a subclass the name of which is "creation".

The user will have to enter information about the "project" he wants to create ... so he will choose between categories, then he will enter, for example, "websites creation".

A form will appear on the next page, asking him to enter all the information about his future website, e.g., h1 color, h2 color, h3 color, paragraphs, logo, description of the website, keywords, number of p开发者_如何学编程ages, site map, etc.

If he chooses the category "flash', he will only describe his futuree animation, e.g., colors, animation_description - but without specifying the h1, h2, etc. like for the "website creation" category.

The admin can add, delete, and update categories. I am asking about how to gather classes with different attributes (colors, h1 , h2, etc) within the same parent class.

Finally , I'd like to mention that the form where the user will enter attributes is also changeable from the admin page according to the attributes required for the category.

Thank you in advance.