When the user clicks any cell within one of the ranges, the background color
(by color index, or any other appropriate color selection system) is
selected. When the user clicks a background-colored cell, the color returns
to White, index 2. We are toggling a color on and off, based on cell
location and color index. What would the code be?

Range Index
S8:AX16 36
S17:AX23 40
S24:AX34 34
S36:AX38 35