Parallax scroll (pure CSS)

by Torwan

HTML

<div class="demo__info">
    Pure CSS parallax scroll demo #3 by Keith Clark (<a href="http://keithclark.co.uk/articles/pure-css-parallax-websites/" target="_blank">see here</a>).
    Demo images from <a href="http://pixabay.com/" target="_blank">http://pixabay.com/</a>
 </div>

<div class="parallax">
    <div id="group1" class="parallax__group">
      <div class="parallax__layer parallax__layer--base">
        <div class="title">Base Layer</div>
      </div>
    </div>
    <div id="group2" class="parallax__group">
      <div class="parallax__layer parallax__layer--base">
        <div class="title">Base Layer</div>
      </div>
      <div class="parallax__layer parallax__layer--back">
        <div class="title">Background Layer</div>
      </div>
    </div>
    <div id="group3" class="parallax__group">
      <div class="parallax__layer parallax__layer--fore">
        <div class="title">Foreground Layer</div>
      </div>
      <div class="parallax__layer parallax__layer--base">
        <div class="title">Base Layer</div>
      </div>
    </div>
    <div id="group4" class="parallax__group">
      <div class="parallax__layer parallax__layer--base">
        <div class="title">Base Layer</div>
      </div>
      <div class="parallax__layer parallax__layer--back">
        <div class="title">Background Layer</div>
      </div>
      <div class="parallax__layer parallax__layer--deep">
        <div class="title">Deep Background Layer</div>
      </div>
    </div>
    <div id="group5" class="parallax__group">
      <div class="parallax__layer parallax__layer--fore">
        <div class="title">Foreground Layer</div>
      </div>
      <div class="parallax__layer parallax__layer--base">
        <div class="title">Base Layer</div>
      </div>
    </div>
    <div id="group6" class="parallax__group">
      <div class="parallax__layer parallax__layer--back">
        <div class="title">Background Layer</div>
      </div>
      <div class="parallax__layer...

CSS

/* Parallax base styles
  --------------------------------------------- */

  .parallax {
    height: 500px; /* fallback for older browsers */
    height: 100vh;
    overflow-x: hidden;
    overflow-y: auto;
    -webkit-perspective: 300px;
    perspective: 300px;
    -webkit-perspective-origin-x: 100%;
    perspective-origin-x: 100%;
  }

  .parallax__group {
    position: relative;
    height: 500px; /* fallback for older browsers */
    height: 100vh;
    -webkit-transform-style: preserve-3d;
    transform-style: preserve-3d;
  }

  .parallax__layer {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    -webkit-transform-origin-x: 100%;
    transform-origin-x: 100%;
  }

  .parallax__layer--fore {
    -webkit-transform: translateZ(90px) scale(.7);
    transform: translateZ(90px) scale(.7);
    z-index: 1;
  }

  .parallax__layer--base {
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
    z-index: 4;
    
  }

  .parallax__layer--back {
    -webkit-transform: translateZ(-300px) scale(2);
    transform: translateZ(-300px) scale(2);
    z-index: 3;
  }

  .parallax__layer--deep {
    -webkit-transform: translateZ(-600px) scale(3);
    transform: translateZ(-600px) scale(3);
    z-index: 2;
  }


  /* demo styles
  --------------------------------------------- */

  body, html {
    overflow: hidden;
  }

  body {
    font: 100% / 1.5 Arial;
  }

  * {
    margin:0;
    padding:0;
  }

  .parallax {
    font-size: 200%;
  }

   /* centre the content in the parallax layers */
  .title {
    text-align: center;
    position: absolute;
    left: 50%;
    top: 50%;
    -webkit-transform: translate(-50%, -50%);
    transform: translate(-50%, -50%);
  }



  /* style the groups
  --------------------------------------------- */

  #group1 {
    z-index: 5; /* slide over group 2 */
    background: url(http://pixabay.com/get/4bb8f61490700a819fea/1428270035/new-york-472393_1920.jpg?direct) no-repeat center center fixed; 
 ...