Written & originally posted by Opfer.

Alright, here comes another Mod allowing you to give each Board and each Category a unique Background-Color (2 different Colors for win and win2), Text-Color, and Background Image. The idea for this mod came from fiik.

This can be used to seperate the categories and boards from each other or to mark certain boards or simply to give it a unique look.

Install guide

1. Upload all files and folders using the directory structure of the zip-file.
2. Go to the Modification Center in the Admin CP and click "Install"

(Don't worry about the overwritten language files, they just add entries into the gaps, except the english.lng which will replace "Color" in the Post-Screen with "Text-Color" which is more correct anyway)

Users manual

2. Where do I change the Background?

Go to your Admin CP, click on "Edit Boards and Categories" then you can edit an existing category or board.

2. New/Edit Category

Category-Color (win):
This is the color of the cell that indicates new posts and the "Topics" and "Posts" cells. This color is only visible when the category is a sub-category that you can see on the board index.

Category-Color (win2):
This is the "main" category background. It's visible for every category. When the category is a sub-cat it will be the "Board-Name" and the "Last Action" cells.

Category-Image:
Here you can give the URL of any Image on the web. If you want a relative path to a file on your server it should look like: "/blahdocs/images/background.gif".

Text-Color:
This is the color of the Text that appears in the category. This can be useful when using dark colors when you have to choose a bright text-color. This doesn't apply for links.

Leaving one of more fields blank will set them to the values defined by the theme.

3. New/Edit Board

Board-Color (win):
This is the color of the cell that indicates new posts and the "Topics" and "Posts" cells.

Board-Color (win2):
This is the "main" board background. It colors the "Board-Name" and the "Last Action" cells.

Background-Image:
Here you can give the URL of any Image on the web. If you want a relative path to a file on your server it should look like: "/blahdocs/images/background.gif".

Text-Color:
This is the color of the Text that appears in the board. This can be useful when using dark colors when you have to choose a bright text-color. This doesn't apply for links.

Leaving one of more fields blank will set them to the values defined by the theme.

Ryan's Edit: The second zip file is for those who have my Board Index layout mod installed.  You must install this Board & Category colors mod AFTER my mod... and uninstall BEFORE my mod.