3-bit color on Bangle.js 2

@Gordon

This code is quite magic - trying to figure it out.

// HSB test
for (var y=0;y<176;y+=4)
  for (var x=0;x<176;x+=4)
    g.setColor.apply(g,E.HSBtoRGB(x/176.0,y/176.0,1,1).map(x=>x/256)).fillRect(x,y,x+3,y+3);

If I wanted a whole screen of a mix blue and cyan - how could I do that ?