Options for the bottom part of window

[Skynet5]

This is a view of the side of the case (core x9). I want to cover the bottom of the window.

I could buy 4x120 RGB fans. For looks only, as it's a window with no vents. Or what else?

Could I get a decent decal? Or an RGB panel?

Ideas ?

 

[Skynet5]

PSU shroud? Folded acrylic like the old days?

Folded acrylic. Like that.