I understand that you need to change the yellow background color that is applied to the RadMenuItem when it is hovered. However, this color is not set using background-color:yellow
but it is rather a sprite image
that is applied to the item when it is hovered. Thus it is not only a single property that you need to overwrite but a whole sprite image that you need to alter and apply instead of the original one. Therefore I recommended the above article that explains how you can alter that color. Another approach would be to use our Visual Style Builder
and implement your own custom skin.
the Telerik team
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