#9900FF

It all comes down to this...

Final day of the roygbiv challenge.

Top left to bottom right we have:
-Red
-Orange
-Yellow
-Green
-Blue
-Indigo
& lastly fading away at the end of the spectrum we have todays Violet.

Made pointing a Swarovski seashell at the setting sun and angling one of the rainbows up onto the dark shaded ceiling.