Playing this game, the monochromatic use of the color blue is one of the first things I noticed. The blues you use are very saturated and reminiscent of the kind used on arcade games. They are bright and eye-catching, giving off the mood that this game will be an upbeat one rather than one filled with melancholy. In the context of the game, I associate the use of blue to be with that of the ocean surrounding the island that the player is stranded on as well as the open blue of the sky. I think its also important that you chose to use the same color palette throughout when you could have changed the tonality of blues to indicate the progression of time on the island as the day goes on or the seasons changing on the island. Instead, by keeping with the same color palette, the player is made to feel as though time is stagnate as they are stuck on the island. The only change we see is the person digging for treasuring going deeper and deeper into the ground as the days go on. The similarity in hues of the blues used in the background tiles I would estimate were purposeful so as to make the player feel like they were in great open waters. The horizon line indicated by the line of waves is the only thing that breaks up the clear blue. There is otherwise no separation between the water and that of the sky, which to me while I was playing the game had me equally edge as the saturation of blues calmed me.