open window 1024, 600
w = peek("winwidth")
h = peek("winheight")
rows = 4
hd = int(h / rows)
mitad = 0


for row = 1 to rows
  if not mitad then
     wd = int(w / (8 * row))
     mitad = wd
  else
     mitad = mitad / 2
  end if
  c = 255 / (w / mitad)
  for n = 0 to (w / mitad)
     color 255 - c * n, 255 - c * n, 255 - c * n
     if mod(row, 2) = 0 color c * n, c * n, c * n
     fill rectangle mitad * n, hd * (row - 1), mitad * (n+1), hd * row
     pause .1
  next n
next row