At present, the MetroTouch scrollbars in the Lightweight RenderMode are dark (almost black). All metro-based skins must have gray scrollbars.

Scrollbars are usually considered part of the browser and users are used to them as they are by default. Thus, using the default browser scrollbars may be the best course of action:

<telerik:RadFormDecorator runat="server" ID="rfd1" RenderMode="Lightweight" ControlsToSkip="Scrollbars" Skin="MetroTouch" />

Alternatively, use a CSS rule like this to unify the metro-based scrolblars (replace MetroTouch with Metro for the Metro skin):

html.RadForm_MetroTouch.rfdScrollBars {
scrollbar-3dlight-color: #cbcbcb;
scrollbar-arrow-color: #787878;
scrollbar-base-color: #787878;
scrollbar-darkshadow-color: #a7a7a7;
scrollbar-face-color: #d5d5d5;
scrollbar-highlight-color: #e6e6e6;
scrollbar-shadow-color: #d5d5d5;
scrollbar-track-color: #f5f5f5; }