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CSS

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CSS Base

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JavaScript

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HTML 

              
                <div class="wrapper">
  <header class="container">
    <h1>Background Image Trickery</h1>
  <p>Scrolling effect with fixed background-attachment.</p>
  </header>

<div class="content container">
  <aside class="sidebar width-1v5">
    <ul>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
    </ul>
    <ul>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!" class="active">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
    </ul>
    <ul>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
      <li><a href="#!">list-item</a></li>
    </ul>
  </aside>

  <main class="main width-4v5">
  <blockquote>According to CSS, any background image that is “fixed” using <code>background-attachment: fixed;</code> is fixed with respect to the <strong>viewport</strong>-- <em>not</em> the element with which the image is associated. <i>Eric Meyer</i></blockquote>
  <p class="intro">
  For more information about <code>background-attachment: fixed</code> see the classic <a href="https://meyerweb.com/eric/css/edge/complexspiral/glassy.html">complexspiral demo</a> by Eric Meyer.</p>
  <h3>Just one background-image</h3>
  <p class="intro">
  The light-blue pattern fragments (in the tiling semi-transparent PNG background-image used here) have a 1px solid (white) border.
  </p>
  <p class="intro">
  The containing elements have different background-colors: when transparent it picks up the white <code>background-color</code> from the <code>HTML</code> element, making the pattern appear as a solid flat pattern. When the same light-blue color from the image as <code>background-color</code> is used, then this will trick the eye by making the pattern-fragments appear as white outlines.
  </p>
  <p>
  Ipsum exercitationem cum dolor aliquam nihil. Deserunt repellendus architecto veniam amet facere. Nam deleniti ipsam inventore culpa debitis? Labore rem fugiat veniam nihil nostrum hic eligendi optio? Officiis libero eos.
  </p>
  <p>
  Ipsum exercitationem cum dolor aliquam nihil. Deserunt repellendus architecto veniam amet facere. Nam deleniti ipsam inventore culpa debitis? Labore rem fugiat veniam nihil nostrum hic eligendi optio? Officiis libero eos.
  </p>
  <p>
  Ipsum exercitationem cum dolor aliquam nihil. Deserunt repellendus architecto veniam amet facere. Nam deleniti ipsam inventore culpa debitis? Labore rem fugiat veniam nihil nostrum hic eligendi optio? Officiis libero eos.
  </p>
  <p>
  Ipsum exercitationem cum dolor aliquam nihil. Deserunt repellendus architecto veniam amet facere. Nam deleniti ipsam inventore culpa debitis? Labore rem fugiat veniam nihil nostrum hic eligendi optio? Officiis libero eos.
  </p>
  <p>
  Ipsum exercitationem cum dolor aliquam nihil. Deserunt repellendus architecto veniam amet facere. Nam deleniti ipsam inventore culpa debitis? Labore rem fugiat veniam nihil nostrum hic eligendi optio? Officiis libero eos.
  </p>
  <p>
  Ipsum exercitationem cum dolor aliquam nihil. Deserunt repellendus architecto veniam amet facere. Nam deleniti ipsam inventore culpa debitis? Labore rem fugiat veniam nihil nostrum hic eligendi optio? Officiis libero eos.
  </p>
  </main>
</div>
<footer class="container"><small><a href="https://codepen.io/atelierbram/bLsjg/">on Codepen</a></small></footer>
</div>
!

CSS 

              
                *,
*:before,
*:after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  /* outline: 1px dotted salmon; */
}
$bg-image: url(https://lh4.googleusercontent.com/-A4EZf9W6K6E/U0mt4WBJb2I/AAAAAAAAA6I/D3qpuIr3NZw/s800/bg-test_codepen_200x200.png);
body,
.wrapper,
.wrapper:after {
  background: $bg-image,linear-gradient(to right,#baf2fd,#baf2fd 200px,transparent 200px,transparent 852px,#baf2fd 852px,#baf2fd);
}
.wrapper:after {
  background-color: #baf2fd;
}
.wrapper:after { content: "";
  position: absolute;
  right:0;left:0;
}
.wrapper:after {
  z-index: -2;
  top:100%;bottom:-100%;
}
header,
h3,
footer {
  background: $bg-image;
  background-color: #fff;
}
blockquote {
  background: $bg-image;
  background-color: hsla(190, 100%, 40%, .1);
  font-size: 1.5em;
  font-style: italic;
  padding: 2em 4%;
  color: #5936e2;
}
blockquote i {
  float: right;
}
.sidebar a {
  background: $bg-image;
}
.sidebar .active,
.sidebar a:hover {
  background-color: hsla(0,0%,100%,.75);
  padding-right: 0;
  padding-left: .75em;
}
body,
.wrapper,
.wrapper:after,
header,
blockquote,
h3,
.sidebar a,
footer {
   background-position: 0 0;
  background-repeat: repeat;
  background-attachment: fixed;
}

/* general styles */
html {
  background-color: #fff;
}
html,
body {
  min-height: 100%;
}
body {
  font: 100%/1.5 AvenirNext-Regular, Corbel, "Lucida Grande", "Trebuchet Ms", sans-serif;
  color: #111;
  position: relative;
}
.container {
  max-width: 54em;
  padding-left: 1.75em;
  overflow: auto;
}
h3 {
  font-size: 1.75em;
  padding: 1em 4% .5em;
}
header h1,
h3 {
  font-family: AvenirNextCondensed-DemiBold, Corbel, "Lucida Grande","Trebuchet Ms", sans-serif;
  color: #006a80;
}
header h1 {
  font-size: 2.5em;
  padding: .5em 0;
}
header h1,
header p,
footer small {
  text-indent: 23%
}
header p {
  font-size: 1.125em;
  margin-bottom: 1em;
}
.sidebar {
  padding: 2em 0 1em;
}
.sidebar ul {
  list-style: none;
  margin: 0 0 2em;
}
a {
  color: #0ac;
  text-decoration: none;
}
a:hover {
  color: #003c4d;
}
.sidebar a {
  display: block;
  padding: .25em;
  transition: all .3s;
}
.content p {
  padding: .5em 4%;
}
.content p {
  background-color: hsla(0,0%,100%,.6);
  color: #aaa;
}
.content .intro {
  color: #111;
  font-size: 1.125em;
}
p code {
  background: #ccc;
  color: #000;
  padding: 3px .5em;
  border-radius: 3px;
  font-family: Consolas, Menlo, Monaco, monospace;
  font-size: .875em;
}
footer {
  text-align: center;
}
footer a {
  padding: 2em 0 3em;
  display: block;
  color: #079;
  text-decoration: none;
}
blockquote,
i {
  font-family: AvenirNext-Italic, AvenirNext-Regular, Corbel, "Lucida Grande", "Trebuchet Ms", sans-serif;
}
em,
blockquote strong {
 font-family: AvenirNext-DemiBoldItalic, AvenirNext-Italic, Corbel, "Lucida Grande", "Trebuchet Ms", sans-serif;
}
@media (min-width:400px) {
  [class*="width-"] {
    float: left;
  }
  .width-1v5 {
    width: 20%;
  }
  .width-3v5 {
    width: 60%;
  }
  .width-4v5 {
    width: 80%;
  }
} 
@media (max-width:400px) {
  .container {
    overflow: hidden;
  }
}
!

JS
!
999px

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