We don't have Orchard-specific themes shipped with Kendo UI by default. Your options would be to choose one of the available themes which resembles most closely the Orchard design and styles, or create your custom theme in conformance with them using our Theme Builder tool
@Steve: You are free to use Kendo UI Core
inside of Orchard, since its permissive Apache 2.0 licensing allows that at no cost. For Kendo UI Professional, you need to adhere to the commercial licensing terms of the product available here
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