Selecting Light did the trick. Thank you!

How do I reverse the black/white gradation bars on the left and bottom of the palette? Currently, my lower left is white on both bars going to black moving up and to the right. Most tutorials I see have the lower left corner as black going to white moving up and to the right.

My Curves palette is displaying with the black/white bars at bottom and left sides reversed. That is the lower left is the pure white instead of pure black as I see everywhere else, including in a tutorial I’m trying to step through. How can I fix this?