@media (max-width: 767px) {
  #sidebar {
    display: none;
  }
}

@media (min-width: 768px) and (max-width: 1023px) {
  #sidebar {
    display: none;
  }
}

@media (max-width: 767px) {
  #main #heading span {
    display: none;
  }
}