Look at the yellow pee in the blue shadown/in the blue glass: Yellow + blue = green. Look at the pee drop in front of the glass which is not in the shadow = Completely yellow.
Hey that's science at work there! *Ahem!* When water that has color is in front of other objects that has different color, they tend to mix. Specially with colored water since it's semi-transparent, so when it is placed in a clear glass and placed on an object with a different color, the color of the water in the glass will show changes in colors due to the color/light refraction from the solid flat object below (for example, the yellow pee + blue shadowed floor). But really, the shadow should have been black and the pee should've showed a blackish-yellow color tone. So this kinda fails on some scale.