int c = int(random(100));
int d = 50;
boolean dr = true;
int last_change;
int delay_sec = 20;

void setup() {
  colorMode(HSB, 100);
  //size(1280, 800);
  size(800, 600);
  background(c, random(40, 100), random(20, 100));
  noStroke();
  last_change = millis();
}

void draw() {
  if (millis() > last_change + delay_sec*1000) {
    c = int(random(100));
    last_change = millis();
  }
  fill(c, random(40, 100), random(20, 100));
  int i = int(random(width/10, width/3));
  
  if (dr) {ellipse(random(width), random(height), i, i);}
  delay(d);
}

void keyPressed() {
  switch(key) {
     case ' ':
      c = int(random(100));
      break;
     case 'p':
     case 'P':
       dr = !dr;
       break;
  }
}