To begin with, I recommend you to take a look at the Appearance and Styling
help article (if you haven't already done so), which outlines the most important CSS classes used across the Kendo widgets.
With regard to icon CSS classes and sprite images, we have no explicit documentation, as tweaking sprites and modifying corresponding styles is generally for front-end developers that are already familiar with the theory and can quickly find what they need. However, if you need to know more about the sprites and styles, you can use the following information:
- line numbers, widgets and sprite images:
205 - 257 : various icons (sprite.png)
2297 - 2313 : Editor icons (sprite.png)
2646 - 2688 : Slider ticks (slider-h.gif and slider-v.gif)
2808 - 2860 : Tooltip callouts (sprite.png)
2995 - 3005 : Splitter icons (sprite.png)
3099 - 3111 : Upload icons (sprite.png)
If you need more information, please explain what are you trying to do, so that I can provide more relevant advice. If needed, I can send you a specified theme's sprite PSD file with layers and guides, so that you can easily see which icon goes where and replace only what you want.
the Telerik team
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