Я пытаюсь добавить эффект параллакса на мою веб-страницу. Мне нужно, чтобы некоторые элементы всплывали, когда пользователь идет дальше и дальше вниз по странице. Я нашел этот исходный код в Интернете и немного его подправил. https://www.superhi.com/blog/how-to-add-web-design-elements-that-fade-in-and-out-on-scroll.
Я могу заставить элементы появиться один раз, но после прокрутки назад на страницу, где элементы уже видны.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="description" content="">
<meta name="author" content="">
<title>Sample Portfolio</title>
<!-- Bootstrap core CSS -->
<link href="css/bootstrap.css" rel="stylesheet">
<!-- Add custom CSS here -->
<!-- <link href="css/animate.css" rel="stylesheet"> -->
<link href="css/stylish-portfolio.css" rel="stylesheet">
<link href="font-awesome/css/font-awesome.min.css" rel="stylesheet">
</head>
<body>
<!-- Side Menu -->
<a id="menu-toggle" href="#" class="btn btn-primary btn-lg toggle"><i class="fa fa-bars"></i></a>
<div id="sidebar-wrapper">
<ul class="sidebar-nav">
<a id="menu-close" href="#" class="btn btn-default btn-lg pull-right toggle"><i class="fa fa-times"></i></a>
<li class="sidebar-brand"><a href="http://startbootstrap.com">Mark Bonilla</a>
</li>
<li><a href="#top">Home</a>
</li>
<li><a href="#about">About</a>
</li>
<li><a href="#portfolio">Portfolio</a>
</li>
<li><a href="#contact">Contact Me</a>
</li>
</ul>
</div>
<!-- /Side Menu -->
<!-- Full Page Image Header Area -->
<div id="top" class="header">
<div class="vert-text">
<h1 class="tago">Profile Name</h1>
<h3>
<em>If</em> you can think it,
<em>We</em> can develop it.</h3>
<!-- <a href="#about" class="btn btn-default btn-lg">Find Out More</a> -->
</div>
</div>
<!-- /Full Page Image Header Area -->
<!-- Intro -->
<div id="about" class="intro">
<div class="container">
<div class="row">
<div class="col-md-12 text-center">
<h2 class="tago">About Me</h2>
<hr>
<p class="lead tago">Lorem Ipsum bla bla bala.</p>
</div>
</div>
<div class="row intro closing">
<div class="col-md-12 text-center">
<h2 class="tago">Experience with</h2>
<hr>
<ul class="list-inline tago slideUp">
<li><img src="img/html.png" alt="HTML" title="HTML" style></li>
<li><img src="img/css.png" alt="CSS" title="CSS" style></li>
<li><img src="img/js.png" alt="JavaScript" title="JavaScript"></li>
<!-- <li><img src="img/wp.png" alt="Wordpress" title="Wordpress"></li> -->
<li><img src="img/git.png" alt="Git" title="Git"></li>
<li><img src="img/ill.png" alt="Adobe XD" title="Adobe Illustrator"></li>
<li><img src="img/ps.png" alt="Adobe Photoshop" title="Adobe Photoshop"></li>
<li><img src="img/pr.png" alt="Adobe Premier Pro" title="Adobe Premier Pro"></li>
</ul>
</div>
</div>
</div>
</div>
<!-- /Intro -->
<!-- Portfolio -->
<div id="portfolio" class="portfolio">
<div class="container">
<div class="row">
<div class="col-md-4 col-md-offset-4 text-center">
<h2 class="tago">Portfolio/Practice works</h2>
<hr>
</div>
</div>
<div class="row">
<div class="col-md-4 col-md-offset-2 text-center">
<div class="portfolio-item">
<a href="#">
<img class="img-portfolio img-responsive" src="img/portfolio-1.jpg">
</a>
<h4>Cityscape</h4>
</div>
</div>
<div class="col-md-4 text-center">
<div class="portfolio-item">
<a href="#">
<img class="img-portfolio img-responsive" src="img/portfolio-2.jpg">
</a>
<h4>Is That On Fire?</h4>
</div>
</div>
</div>
<div class="row">
<div class="col-md-4 col-md-offset-2 text-center">
<div class="portfolio-item">
<a href="#">
<img class="img-portfolio img-responsive" src="img/portfolio-3.jpg">
</a>
<h4>Stop Sign</h4>
</div>
</div>
<div class="col-md-4 text-center">
<div class="portfolio-item">
<a href="#">
<img class="img-portfolio img-responsive" src="img/portfolio-4.jpg">
</a>
<h4>Narrow Focus</h4>
</div>
</div>
</div>
<div class="row">
<div class="col-md-4 col-md-offset-2 text-center">
<div class="portfolio-item">
<a href="#">
<img class="img-portfolio img-responsive" src="img/portfolio-3.jpg">
</a>
<h4>Stop Sign</h4>
</div>
</div>
<div class="col-md-4 text-center">
<div class="portfolio-item">
<a href="#">
<img class="img-portfolio img-responsive" src="img/portfolio-4.jpg">
</a>
<h4>Narrow Focus</h4>
</div>
</div>
</div>
</div>
</div>
<!-- /Portfolio -->
<!-- Contact Me -->
<div id="contact" class="intro">
<div class="container">
<div class="row">
<div class="col-md-12 text-center">
<h2 class="tago">Contact Me</h2>
<hr>
<p class="lead tago">If you're interested in collaborating or getting my services. You can contact me throught the following:</p>
<div class="col-md-6 col-md-offset-3 text-center">
<ul class="list-inline intro">
<li><a href="https://www.facebook.com/markbrian.bonilla" class="fa fa-facebook fa-5x icons-social" style="text-decoration: none" target="_blank"></a>
</li>
<li><a href="https://www.linkedin.com/in/mark-brian-bonilla-266387167/" class="fa fa-linkedin fa-5x icons-social" style="text-decoration: none" target="_blank"></a>
</li>
<li><a href="https://dribbble.com/bonykid16" class="fa fa-dribbble fa-5x icons-social" style="text-decoration: none" target="_blank" ></a>
</li>
</ul>
<div>
<a class="resume-link" href="file/markresume.pdf" target="_blank"><img src="img\resume.png"></a>
</div>
<p class="lead tago"><strong>Phone:</strong> +(63)92775529580</p>
<p class="lead tago"><strong>Email:</strong> iammarkbonilla@gmail.com
</div>
</div>
</div>
</div>
</div>
<!-- /Contact Me -->
<!-- Footer -->
<div class="footer group">
<div class="row text-center">
<p class="lead">2020 All Rights Reserved.</p>
</div>
</div>
<!-- /Footer -->
<!-- JavaScript -->
<!-- <script src="js/jquery-1.10.2.js"></script> -->
<script src="https://code.jquery.com/jquery-3.3.1.min.js" integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script>
<script src="js/bootstrap.js"></script>
<script>
$(document).on("scroll", function () {
var pageTop = $(document).scrollTop()
var pageBottom = pageTop + $(window).height()
var tago = $(".tago")
for (var i = 0; i < tago.length; i++) {
var tag = tago[i]
if ($(tag).position().top < pageBottom) {
$(tag).addClass("visible")
} else {
$(tag).removeClass("visible")
}
}
})
</script>
</body>
</html>
$(document).on("scroll", function () {
var pageTop = $(document).scrollTop()
var pageBottom = pageTop + $(window).height()
var tago = $(".tago")
for (var i = 0; i < tago.length; i++) {
var tag = tago[i]
if ($(tag).position().top < pageBottom) {
$(tag).addClass("visible")
} else {
$(tag).removeClass("visible")
}
}
})
.tago {
opacity: 0;
transform: translate(0, 20px);
transition: all 1s;
}
.slideUp {
transform: translate(0, 100px);
}
.tago.visible {
opacity: 1;
transform: translate(0, 0);
}
<!-- Intro -->
<div id="about" class="intro">
<div class="container">
<div class="row">
<div class="col-md-12 text-center">
<h2 class="tago">About Me</h2>
<hr>
<p class="lead tago">I graduated from Bulacan State University. I worked in the BPO industry for about 6 years after graduating, but wasn't too fond of it. I started spending every second of my free time learning to code and after I quit my work and from there I've learned how to develop web pages from scratch. Turn ideas into good projects.</p>
</div>
</div>
<div class="row intro closing">
<div class="col-md-12 text-center">
<h2 class="tago">Experience with</h2>
<hr>
<ul class="list-inline tago slideUp">
<li><img src="img/html.png" alt="HTML" title="HTML" style></li>
<li><img src="img/css.png" alt="CSS" title="CSS" style></li>
<li><img src="img/js.png" alt="JavaScript" title="JavaScript"></li>
<!-- <li><img src="img/wp.png" alt="Wordpress" title="Wordpress"></li> -->
<li><img src="img/git.png" alt="Git" title="Git"></li>
<li><img src="img/ill.png" alt="Adobe XD" title="Adobe Illustrator"></li>
<li><img src="img/ps.png" alt="Adobe Photoshop" title="Adobe Photoshop"></li>
<li><img src="img/pr.png" alt="Adobe Premier Pro" title="Adobe Premier Pro"></li>
</ul>
</div>
</div>
</div>
</div>
<!-- /Intro -->
Любая помощь очень ценится.