1. customizable colours
2. minimize, maximize and close icons
3. another way of painting window titles
Here is the screenshot:
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The default colour is soft green, but you can change it to anything you like by selecting the "Selected Item" colour in the Themes Customization menu (System - Preferences - Theme - Customize - Colors)
Credits: bvc - close, minimize, maximize and unmaximize icons;
Daniel Borgmann, Billy Cantrell, Richard Stellingwerff - original Human theme files.
Download from here.
How to install a Desktop theme.