this.setBackground(Color.white); // The applet is white
this.setFont(new Font("Dialog", Font.BOLD, 24));
Panel p1 = new Panel();
p1.setBackground(new Color(200, 200, 200)); // Panel1 is darker than applet
this.add(p1); // Panel 1 is contained in applet
p1.add(new Button("#1")); // Button 1 is contained in Panel 1
Panel p2 = new Panel();
p2.setBackground(new Color(150, 150, 150)); // Panel2 is darker than Panel1
p1.add(p2); // Panel 2 is contained in Panel 1
p2.add(new Button("#2")); // Button 2 is contained in Panel 2
Panel p3 = new Panel();
p3.setBackground(new Color(100, 100, 100)); // Panel3 is darker than Panel2
p2.add(p3); // Panel 3 is contained in Panel 2
p3.add(new Button("#3")); // Button 3 is contained in Panel 3
Panel p4 = new Panel();
p4.setBackground(new Color(150, 150, 150)); // Panel4 is darker than Panel1
p1.add(p4); // Panel4 is contained in Panel 1
p4.add(new Button("#4")); // Button4 is contained in Panel4
p4.add(new Button("#5")); // Button5 is contained in Panel4
this.add(new Button("#6")); // Button6 is contained in applet