#world_d{
  background-image : url(world/worldback_01.jpg);
  background-attachment: fixed;
  background-repeat : no-repeat;
  background-position : right bottom;
}
#world_f{
  background-image : url(world/worldback_02.jpg);
  background-attachment: fixed;
  background-repeat : no-repeat;
  background-position : right bottom;
}