After watching this art it seems like to me that A dark cave filled with water .
This cave wait everyday for some light. But the light always come from opposition way. But the water helps that cave to light up. So, when the light reflect on the water , Water make a beautiful reflection on the cave and the light is reflecting like crystal clear . But there are some deep place in the cave where water lighting reflection can't arrive .
@velimir That's all my useless imagination : )