@media screen and (max-width: 999px){
  .jobOne{
    width: 100%;
    height: 1800px;
  }
  .jobOneBig{
    display: none;
  }
}
@media screen and (min-width: 999px) {
  .jobOneBig {
    width: 980px;
    height: 1800px;
  }

  .jobOne {
    display: none;
  }
}