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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class="panel" data-color="white">
      <h1>Magic scrolling colours</h1>
      <p>Scroll to animate the background colour of the body as a full height panel becomes visible.</p>
      <p>I have tried to comment the code, particurly the JavaScript, as much as possible. I hope it's clear to understand.</p>
      <p>If you have any questions my twitter is <a href="">@daveredfern</a>.</p>
<div class="panel" data-color="violet">
  <h2>Violet panel</h2>
<div class="panel" data-color="indigo">
  <h2>Indigo panel</h2>
<div class="panel" data-color="blue">
  <h2>Blue panel</h2>
<div class="panel" data-color="green">
  <h2>Green panel</h2>
<div class="panel" data-color="yellow">
  <h2>Yellow panel</h2>
<div class="panel" data-color="orange">
  <h2>Orange panel</h2>
<div class="panel" data-color="red">
  <h2>Red panel</h2>
              /* Setting fade transition and default settings */
body {
  color: #000;
  background-color: #f4f4f4;
  transition: background-color 1s ease;

/* panel styles */
.panel {
  /* min height incase content is higher than window height */
  min-height: 100vh;
  display: flex;
  justify-content: space-around;
  align-items: center;
  font-family: sans-serif;
  /* outline: 10px solid hotpink; */
  /* turn above on to see the edge of panels */

/* colours */
.color-violet {
  background-color: #7A4EAB;
.color-indigo {
  background-color: #4332CF;
.color-blue {
  background-color: #2F8FED;
.color-green {
  background-color: #4DCF42;
.color-yellow {
  background-color: #FAEB33;
.color-orange {
  background-color: #F19031;
.color-red {
  background-color: #F2293A;

/* styling for demo, can ignore */
body {
  text-align: center;
  font-size: 120%;
  line-height: 1.618;
h1, h2 {
  font-size: 3em;
  letter-spacing: -0.05em;
  line-height: 1.1;
p {
  max-width: 30em;
  margin-bottom: 1.618em;
a {
  color: #4332CF;
              $(window).scroll(function() {
  // selectors
  var $window = $(window),
      $body = $('body'),
      $panel = $('.panel');
  // Change 33% earlier than scroll position so colour is there when you arrive.
  var scroll = $window.scrollTop() + ($window.height() / 3);
  $panel.each(function () {
    var $this = $(this);
    // if position is within range of this panel.
    // So position of (position of top of div <= scroll position) && (position of bottom of div > scroll position).
    // Remember we set the scroll to 33% earlier in scroll var.
    if ($this.position().top <= scroll && $this.position().top + $this.height() > scroll) {
      // Remove all classes on body with color-
      $body.removeClass(function (index, css) {
        return (css.match (/(^|\s)color-\S+/g) || []).join(' ');
      // Add class of currently active div
      $body.addClass('color-' + $(this).data('color'));
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