Set scrollbar background color in light and medium modes

The scrollbar background in both light and medium is white, thereby being practically indistinguishable from the workspace while doing most works. It would be great if it'd have a color so I (and perhaps others too) wouldn't keep accidentally clicking it instead of the workspace when something is close to the edge.

In the Appearance settings we can set the window and desktop color, a scrollbar color setting could fit there nicely.