size(300,300);


stroke(0,250,0);
rect(150,150,100,100);

stroke(0,0,250);
rect(160,160,80,80);

stroke(0,0,250);
rect(170,170,60,60);

stroke(0,250,0);
rect(180,180,40,40);

stroke(0,250,0);
rect(190,190,20,20);




stroke(0,0,250);
rect(25,25,40,40);

fill(250,250,250);
rect(5,5,20,20);


stroke(0,0,250);
line(10,10,10,280);
line(10,280,280,280);
line(280,280,280,10);
line(280,10,10,10);

stroke(255,0,0);
line(140,140,140,160);
line(140,160,160,160);
line(160,160,160,140);
line(160,140,140,140);

stroke(255,0,0);
line(130,130,130,170);
line(130,170,170,170);
line(170,170,170,130);
line(170,130,130,130);

stroke(255,0,0);
line(135,135,135,175);
line(135,175,175,175);
line(175,175,175,135);
line(175,135,135,135);

stroke(0,250,0);
line(120,120,120,180);
line(120,180,180,180);
line(180,180,180,120);
line(180,120,120,120);

stroke(0,250,0);
line(30,30,30,260);
line(30,260,260,260);
line(260,260,260,30);
line(260,30,30,30);