Rect random colors

int x = 0;
int sizeX = 50;
int sizeY = 50;

void setup(){
  size(600,600);
  background(255);

}
void draw(){
  noLoop();
  for(int rows = 0; rows < 600; rows = rows + 50){
    for(int cols = 0; cols<600; cols = cols+ 50){
float r = random(0,225);
float g = random(0,255);
float b = random(0,255);
    rect(rows, cols, sizeX, sizeY);
    fill(r, g, b);

    }}
}