Material theme concept uses two colors, a primary one and a secondary one, and the rest of the colors are derived from them - Material design Color Palette
. As Material Menus are white
, we have created a white RadMenu. There is no option to change just the Material Menu background through the Theme Builder application. The good news is that we are about to release a new Theme Builder application, which would allow creation of dark Material custom themes, as well as it provides several predefined color swatches. For the time being, I would recommend you to customize Material theme with it using Chrome or Firefox browsers.
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