55

size(400,315);
for(int i =0; i < height; i += width/15){
float r = random(255);
float g = random(255);
float b = random(255);
for(int j =0, a = 255; j < width; j += width/10, a*= .8){
strokeWeight(5);
stroke(0,a);
fill(r,g,b,a);
rect(j,i,width/10,width/10);
}

}