First I would like to clarify that we suggest using CSS styles in order to customize the HTML elements instead of using the RadMenu server-side properties such as BorderColor="Black" and etc.. The CSS gives you more options for styling the layout or formatting the HTML elements on the page. In order to make that process easier when using our controls we are applying different CSS classes to the rendered elements. Here you may find the RadMenu CSS selectors.
Also it is a good practice to separate your styles in external CSS files.
Handler icons in RadMenu with a lightweight render mode are visualized by using font icons instead of sprites. This feature gives you an ability to customize size or color of handler icons in easy way. Instead of creating your custom sprite you can modify it simply by overwriting CSS rules.
Please, find a sample solution in the attachment.
Important: Please, keep in mind, that all menus rendered on one page have to be in the same render mode.
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