a.navbar-brand.logout {
    display: none;
}

@media only screen and (max-width: 1000px) {
  img.banner {
    width:100%;
  }
  .welcome-container{
    display: none;
  }
  a.navbar-brand.logout {
    display: block;
  }
}

@media only screen and (max-width: 600px) {
  img.banner {
    width:100%;
  }
  .welcome-container{
    display: none;
  }
  a.navbar-brand.logout {
    display: block;
  }
}