.parallax {
  perspective: 1px;
  height: 100vh;
  overflow-x: hidden;
  overflow-y: auto;
  width: 100%;
      height: 100%;
      background-image: url(ext/bg_grid.png);
          
      background-repeat: repeat;
          
          
      background-position: center;
          
      background-attachment: scroll;
      background-size: 100%;
}
.parallax__layer {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  
}
.parallax__layer--base {
  transform: translateZ(0px);
}
.parallax__layer--back {
  transform: translateZ(-1px);
  
  

}