Tips: Go to a colornumber, keep pushing on the left mouse-button and drag the mouse over the colornumbers, to see the colornumbers in the opposite color.   
On your keyboard: Ctrl and '+' = Zoom-in, Ctrl and '-' = Zoom-out. Click on the hex-colornumber for more lighter or darker colors.

Colorbrowser - Part 2 of 2 - from #7F FF FF to #00 00 00

Optional view : White Text & Black Background