The Skin Builder is a tool which helps you to define any color schema for the interface of dhtmlxScheduler used in your application.
You can choose some preset color scheme from the available list or create your own. When editing skin colors you need to press Apply button to see the result.
When you choose a preset, the preview will be reloaded automatically with new settings.
Detailed Mode (see the button on top) offers more options for customization.
When you got a color scheme you like, click Download button to get a zip file with all necessary files (css and images).
All you need is to replace exising css file and imgs folder inside codebase directory of dhtmlxScheduler.