Need help with dynamic CSS (variable in url?)

I’ve got a site with lets say 8 categories. 4 of these will be duplicated and the content changed, 4 stay the same. What I’m trying to accomplish is to have two distinct themes (two different css files), so that the document tree structure would appear to be like this:
-Summer:
- page 1
- page 2
- page 3
- page 4
- page 5
- page 6
- page 7
- page 8
-Winter:
- page 1
- page 2
- page 3
- page 4
- page 5
- page 6
- page 7
- page 8

but in fact pages 5-8 are always the same document (easier to update and manage), only the css file changes. Pages 1-4 are different documents for different seasons. So in reality, the document tree looks like this:

-Summer:
- page 1
- page 2
- page 3
- page 4
- page 5
- page 6
- page 7
- page 8
-Winter:
- page 1
- page 2
- page 3
- page 4

I’m having trouble wrapping my head around how I would go about doing this. I think I need something like a variable that I can call in the url, so that I can choose between linking to the document with summer theme or with a winter theme. Any ideas? Thanks.

You can use a tv to output a id in the html,



- and in the css make the styling.

^^^ quote

I just doing the same thing for a website about holidays (Christmas, Halloween...).

I need to change only some elements (box background, H1 title backgrounds)

I’m using the class instead the id.

IE

Create a TV
Name : CssClass
Input Type:: Drop down list menu
Input Option Values: select||Summer||Winter||.... (all your classes for categories)
Default Value: @INHERIT


add the class to your code
<div id ="box" class="CssClass">

Now you can select the class for the categories from the TV and all subdocuments will get the class from the parent folder with @INHERIT.

Thanks, friends. We just got a call from the client and it might be that we are dropping the two-season idea, but I’m bound to run into another project like this someday, so thanks for your help!