module T(l,rx,ry,x,y,z,c) {
    color(c) translate([x,y,z]) rotate([rx*90,ry*90,0]) cube([20,20,l], center=false);
}
module S(z) {
    T(2000,0,1,  20,  0,z*450,"Red");
    T(2000,0,1,  20,500,z*450,"Red");
}

T(1800,0,0,2020,  0,0,"Yellow");
T(1800,0,0,2020,500,0,"Yellow");
T(1800,0,0,   0,500,0,"Yellow");
T(1800,0,0,   0,  0,0,"Yellow");

T(600,-1,0,   0,-40,   0,"Orange");
T(600,-1,0,2020,-40,   0,"Orange");
T(500,-1,0,2020, 10,1820,"Orange");
T(500,-1,0,   0, 10,1820,"Orange");

S(1); S(2); S(3); S(4);