Content Switcher for summer winter

Hello all

I am currently trying to create a summer/winter swtich for a website.

I have tried using theme switching plugins, but they don’t seem to be using the new style sheet, and I can’t have multiple content to switch between.

I thought also about using a theme switcher with conditional logic for the menu so that there would be a different menu for each theme based on tags.

None of this really seems to work though, so I was wondering if anyone had any thoughts or ideas in this area to point me in the right direction for plugins or further reading?

Any help very much appreciated.

Best

Harry