#co_buy_a_new_sub_desktop {
  display: inline-block;
}

#co_buy_a_new_sub_mobile {
  display: none;
}

@media (max-width: 768px) {
  #co_buy_a_new_sub_desktop {
    display: none;
  }
  #co_buy_a_new_sub_mobile {
    display: inline-block;
  }
}