Wave box

First you find a piece of wood with figure like a wave. (pic 1)

Then since its front is curved, you make the box-front curved to match. (pic 2)

Then to make the back interesting, you curve that too. In the other direction. (pic 3).
“adds movement” I think would be the term.

Then you make some wave-shaped leather hinges.

Then you make a divider and a tray. With blue (for water! of course) satin padded bottom.

The curved-in box-back and curved-out lid-back make a nice lid stop.