#parallax {
  width: 100%;
  height: 33%;
  min-height: 250px;

  overflow: hidden;
  position: relative;

  border-top: 1px solid #808080;
  border-bottom: 1px solid #808080;
}

#parallax img {
  top: 0;
  left: 0;
  position: absolute;
}

#parallax img.foreground {
  /* NO-OP */
}
  
#parallax img.background {
  width: 100%;
  height: auto;

  top: calc((100% + 80px) / 2);
  transform: translateY(-50%) translateZ(-1px) scale(2.1);
}