Black-Out Mode for viewing images cleanly without the UI

One of my favorite mode's when I used to use Adobe Lightroom was the ability to dim the UI to see just the image, or images, cleanly on the screen and without the user interface. Lightroom allows for this in 2 or 3 increments; each click of the hotkey dims the entire UI surrounding the selected/viewing image/s by 50% gray, until the last keystroke - which is black surrounding the image/s.
Capture One could take this a step further by allowing the user to choose between gray, black, or white - giving us the ability to judge and gauge our color grades and image modifications against a clean background . . . example: white for gauging color or B&W images, black to judge contrast, etc.
Would LOVE to see this handy, simple tool ported into C1 Pro!! - or, for that matter, all of the C! versions. PLEASE!