body {
   background: #666;
}

h1 {
   font-size: 200px;
   font-family: sans-serif;
   position: relative;
   color: #a6a6a6;
   text-shadow: 0 -1px 0 white;
}

h1::after {
   content: attr(data-text);
   position: absolute;
   left: 0;
   color: white;
   -webkit-mask-image: -webkit-gradient(
      linear,
      left top, left bottom,
      from(rgba(0,0,0,1)),
      color-stop(40%, rgba(0,0,0,0)),
      to(rgba(0,0,0,0))
   );
}