html, body, #gallery {
  height: 100%;
}

body.split-screen #listing {
  height: 100%;
  width: 50%;
  float: left;
  overflow: auto;
}

body.split-screen #gallery {
  width: 50%;
  float: right;
}
/*
@media screen and (min-width: 1800px) {
  #listing {
    float: left;
    width: 800px;
    height: 100%;
    overflow: auto;
  }

  #gallery {
    margin-left: 800px;
  }

  body.gallery-expanded #listing {
    display: none;
  }

  body.gallery-expanded #gallery {
    margin-left: 0;
  }
}*/