If you're going to use a css widget, you should place the css styles (for the navigation) and the images, referenced in them, outside the App_Data folder (for example in the root), because the App_Data folder has special permissions and this might be the reason why the.css files won't load. Also, if you decide to put them in the root, make sure to rename the images folder to something different than images
(don't forget to change the URL path in the stylesheet as well after you do that), because the name Images is reserved for Sitefinity.
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
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