.bg-header {
  width: 100%;
  height: 300px;
  content: "";
  position: absolute;
  background: rgba(0,0,0,0.8);
  background: -moz-linear-gradient(top, rgba(0,0,0,0.8) 0%, rgba(0,0,0,0) 100%);
  background: -webkit-gradient(left top, left bottom, color-stop(0%, rgba(0,0,0,0.8)), color-stop(100%, rgba(0,0,0,0)));
  background: -webkit-linear-gradient(top, rgba(0,0,0,0.8) 0%, rgba(0,0,0,0) 100%);
  background: -o-linear-gradient(top, rgba(0,0,0,0.8) 0%, rgba(0,0,0,0) 100%);
  background: -ms-linear-gradient(top, rgba(0,0,0,0.8) 0%, rgba(0,0,0,0) 100%);
  background: linear-gradient(to bottom, rgba(0,0,0,0.8) 0%, rgba(0,0,0,0) 100%);
  z-index: 3;
}