#services-parallax,
#about-us-parallax { 
  position: relative;
} 
#services-parallax::after,
#about-us-parallax::after { 
  content: "";
  background-color: rgba( 0, 0, 0, 0.5 );
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  position: absolute;
} 
#services-parallax > div,
#about-us-parallax > div { 
  z-index: 9;
}