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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.

            
              <header>
		<h1>Simple JavaScript parallax effect </h1>

		<p>The numbers displayed below represent the "distance" value given to the elements via their class name. Items that are "farther away" and thus scroll slower are given a class name such as far7. "Closer" items that scroll faster are given a name such as near3 (which represents the value 0.3). Distance can be set to any value from 0 (except not actually 0) to infinity. </p>

		<p>The higher the number the less the item will move on scrolling. An item with the value of 1 will scroll as if it was a non parallax item. Items set less than 1 scroll faster than the normal rate </p>

		<p>Parallax items must be set to 'position: relative' in the CSS.</p>

		<h2>Potential Problems</h2>
		<p>This current code can only handle one set of parallax items. The script calculates a vertical offset value that lines up the items to their default positions when they are near the center of the screen. Having multiple sets of parallax items would necessitate calculating multiple vertical offsets, which the code is currently not capable of handling.</p>
		<p>You cannot set the vertical position of the element using the top property in css, since the JavaScript will override it. You need to set the default vertical position of the element using other means, or modify the script to account for the element's initial position.</p>

	</header>

	<section id="parallax">
		<div class="spacer"></div>
		<ul id="parallist">
			<li class="parallitem far10">10</li>
			<li class="parallitem far9">9</li>
			<li class="parallitem far8">8</li>
			<li class="parallitem far7">7</li>
			<li class="parallitem far6">6</li>
			<li class="parallitem far5">5</li>
			<li class="parallitem far4">4</li>
			<li class="parallitem far3">3</li>
			<li class="parallitem far2">2</li>
			<li class="parallitem far1">1</li>
			<li class="parallitem near9">.9</li>
			<li class="parallitem near8">.8</li>
			<li class="parallitem near7">.7</li>
			<li class="parallitem near6">.6</li>
			<li class="parallitem near5">.5</li>
			<li class="parallitem near4">.4</li>
			<li class="parallitem near3">.3</li>
			<li class="parallitem near2">.2</li>
			<li class="parallitem near1">.1</li>
		</ul>
		
	</section>
<section id="extra"></section>
            
          
!
            
              
header {
	height: 500px;
}


header {
	background-color: #B598A2;
}
#parallax {
	background-color: #73799E;
  height: 2500px;
	overflow: hidden;
}

#extra {
  background-color: #809E90;
  height: 500px;
}

#parallist li {
	font-size: 3em;
	display: inline-block;
	text-align: center;
	width: 4.5%;
	position: relative;
}

.spacer {
	height: 1150px;
}

            
          
!
            
              window.addEventListener("scroll", function() {
	var eOffset = document.getElementById("parallist").offsetTop; //finds the distance in pixels the list of parralax items is from the top
	var winHalf = window.innerHeight / 2; //finds the window height and halves it

	var pOffset = document.body.scrollTop - eOffset + winHalf; //Sets the offset value that will ensure the items are lined up when they are in the middle of the screen

	var pItems = document.getElementsByClassName("parallitem");

	for (i=0; i<pItems.length; i++) {
		var pClasses = pItems[i].className;

		if (pClasses.search("far")>-1) {
			var pDist = Number(pClasses.substr(pClasses.indexOf("far")+3));
		}
		else if(pClasses.search("near")>-1) {
			var pDist = Number("." + pClasses.substr(pClasses.indexOf("near")+4));
		}
		else {
			alert("Parallax elment has no set distance");
		} // if statement that determines the parallax distance set by a class name


		pItems[i].style.top = pOffset - pOffset / pDist + "px"; //sets the top position to produce the parallax effect
		 
	}
	
});
            
          
!
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