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HTML

About HTML Preprocessors

HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

Learn more · Versions

Adding Classes

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. So you don't have access to higher-up elements like the <html> tag. If you want to add classes there that can affect the whole document, this is the place to do it.

About the <head>

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. If you need things in the <head> of the document, put that code here.

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Insecure Resource

The resource you are linking to is using the 'http' protocol, which may not work when the browser is using https.

CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

Learn more · Versions

CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

Add External Stylesheets/Pens

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About External Resources

You can apply CSS to your Pen from any stylesheet on the web. Just put a URL to it here and we'll apply it, in the order you have them, before the CSS in the Pen itself.

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

Learn more · Versions

Babel includes JSX processing.

Add External Scripts/Pens

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About External Resources

You can apply a script from anywhere on the web to your Pen. Just put a URL to it here and we'll add it, in the order you have them, before the JavaScript in the Pen itself.

If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.

You can also link to another Pen here, and we'll pull the JavaScript from that Pen and include it. If it's using a matching preprocessor, we'll combine the code before preprocessing, so you can use the linked Pen as a true dependency.

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Packages

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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About Packages

Using packages here is powered by Skypack, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ES6 import usage.

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HTML 

              
                .tl-wrapper
  ul.timeline
    li(data-year="1981").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1988").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1989").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!
          
    li(data-year="1990").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!
          
    li(data-year="1991").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1992").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1993").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1994").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1995").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1996").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1997").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1998").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="1999").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2000").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2001").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2002").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2003").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2004").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2005").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2006").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2007").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!

    li(data-year="2008").tl-item
      .tl-image
        img(src=" http://placehold.it/1650x1000/")
      .tl-copy
        h3.title
          | Aw, you're all Mr. Grumpy Face today. They're not aliens, they're Earth&hellip;liens!
        .tl-description
          p Aw, you're all Mr. Grumpy Face today. No&hellip; It's a thing; it's like a plan, but with more greatness. They're not aliens, they're Earth&hellip;liens! Sorry, checking all the water in this area; there's an escaped fish. All I've got to do is pass as an ordinary human being. Simple. What could possibly go wrong? You've swallowed a planet!
!

CSS 

              
                // Colors
$bg: #289ecb;
$line: #b2e9ff;
$wrapper: #e4f0f4;

//Transition
$t1: .6s ease;

%clearfix {
  content: "";
  display: table;
  clear: both;
}

html {
  font-family: 'Oxygen', sans-serif;
}

*,
*:after,
*:before {
  box-sizing: border-box;
}

// Images will always fit the height of the timeline
img {
  width: auto;
  height: auto;
  max-height: 100%;
}

h3 {
  font-size: 40px;
  margin-top: 0;
  font-weight: 300;
}

/*** The timeline styles and structure ***/
.tl-wrapper {
  background: $wrapper;
  min-height: 1px;
  position: relative;
}

.timeline {
  position: relative;
  width: 100%;
  min-height: 1px;

  list-style: none;
  margin: 0;
  padding: 0;
  li {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    &:after {
      @extend %clearfix;
    }
  }
}

/*** The items ***/
.tl-item {
  visibility: hidden;
  overflow: hidden;
  z-index: 0;
  .tl-copy {
    transition: $t1;
    //opacity: 0;
    transform: translate3d(60%,0,0);
  }
  .tl-image {
    transition: $t1;
    //opacity: .5;
    transform: translate3d(0,-100%,0);
  }
}

.tl-item.tl-active {
  visibility: visible;
  z-index: 10;
  .tl-copy {
    opacity: 1;
    transform: translate3d(0,0,0);
  }
  .tl-image {
    opacity: 1;
    transform: translate3d(0,0,0);
  }
}

// Image's container
.tl-image {
  float: left;
  width: 70%;
  img {
    display: block;
  }
}

// Copy's styles
.tl-copy {
  width: 30%;
  height: 100%;
  position: absolute;
  top: 0;
  right: 0;
  
  padding: 16px;
  padding: 1rem;
  background: $bg;
  color: #fff;
  &:after {
    content: "";
    position: absolute;
    bottom: 30px;
    left: -19px;
    
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 21px 20px 21px 0;
    border-color: transparent $bg transparent transparent;
  }
}

/*** The arrows for the items ***/
.tl-items-arrow-left,
.tl-items-arrow-right {
  position: absolute;
  top: 50%;
  width: 22px;
  height: 40px;
  top: 50%;
  margin-top: -40px;
  z-index: 100;
  &:before,
  &:after {
    content: "";
    display: block;
    position: absolute;
    left: 0;
    width: 28px;
    height: 2px;
    background: #fff;
  }
}
.tl-items-arrow-left {
  left: 0;
  &:before {
    top: 0;
    transform-origin: top right;
    transform: rotate(-45deg);
  }
  &:after {
    bottom: 0;
    transform-origin: bottom right;
    transform: rotate(45deg);
  }
}
.tl-items-arrow-right {
  right: 0;
  &:before {
    top: 0;
    transform-origin: top left;
    transform: rotate(45deg);
  }
  &:after {
    bottom: 0;
    transform-origin: bottom left;
    transform: rotate(-45deg);
  }
}

/*** The nav's styles ***/
.tl-nav-wrapper {
  position: absolute;
  bottom: 10px;
  left: 0;
  margin: 0;
  padding: 16px 0 0 0;
  
  border-top: 1px solid $line;
  overflow-x: hidden;
  width: 100%;
  &:before,
  &:after {
    content: "";
    width: 38px;
    height: 86px;
    position: absolute;
    top: 17px;
    
    background: $wrapper;
    z-index: 50;
  }
  &:before { left: 0; }
  &:after { right: 0; }
}

.no-csstransforms .tl-nav-wrapper {
  overflow-x: auto;
}

.tl-nav {
  list-style: none;
  margin: 0;
  padding-top: 16px;
  border-top: 1px dashed $bg;
  
  transition: all .4s ease;
  li {
    width: 70px;
    height: 70px;
    position: relative;
    
    float: left;
    cursor: pointer;
    margin-right: 1rem;
    
    font-size: 12px;
    text-align: center;
    div {
      width: 34px;
      height: 34px;
      margin: auto;
      
      background: $bg;
      color: #fff;
      padding-top: 9px;
      border-radius: 1000px;
      transition: $t1;
    }
    &:hover div,
    &.tl-active div{
      width: 70px;
      height: 70px;
      background: transparent;
      color: $bg;
      border: 1px solid $bg;
      font-size: 24px;
      padding-top: 19px;
    }
    &:before {
      content: "";
      width: 4px;
      height: 4px;
      position: absolute;
      top: -10px;
      left: 50%;
      margin-left: -2px;
      
      background: $bg;
      border-radius: 1000px;
    }
  }
  &:after {
    @extend %clearfix;
  }
}

/*** The nav's nav styles ***/
.tl-nav-arrow-left,
.tl-nav-arrow-right {
  position: absolute;
  width: 12px;
  height: 20px;
  top: 50%;
  z-index: 100;
  &:before,
  &:after {
    content: "";
    display: block;
    position: absolute;
    width: 14px;
    height: 2px;
    background: $bg;
  }
}
.tl-nav-arrow-left {
  left: 9px;
  &:before {
    top: 0;
    transform-origin: top right;
    transform: rotate(-45deg);
  }
  &:after {
    bottom: 0;
    transform-origin: bottom right;
    transform: rotate(45deg);
  }
}
.tl-nav-arrow-right {
  right: 9px;
  &:before {
    top: 0;
    transform-origin: top left;
    transform: rotate(45deg);
  }
  &:after {
    bottom: 0;
    transform-origin: bottom left;
    transform: rotate(-45deg);
  }
}

.no-csstransforms .tl-nav-arrow-left,
.no-csstransforms .tl-nav-arrow-right {
  display: none;
}
!

JS 

              
                /*** Detect the browser's prefixes ***/ 
if(document.addEventListener){ // Only IE9+ support this ;)
  // http://davidwalsh.name/vendor-prefix
  // Can't use it in IE8- as it brakes the page...
  var isPrefixed = (function () {
    var styles = window.getComputedStyle(document.documentElement, ''),
      pre = (Array.prototype.slice
        .call(styles)
        .join('') 
        .match(/-(moz|webkit|ms)-/) || (styles.OLink === '' && ['', 'o'])
      )[1],
      dom = ('WebKit|Moz|MS|O').match(new RegExp('(' + pre + ')', 'i'))[1];
    return {
      dom: dom,
      lowercase: pre,
      css: '-' + pre + '-',
      js: pre[0].toUpperCase() + pre.substr(1)
    };
  })();

  // Deals with prefixes
  var prefix = isPrefixed.css;

} else {
  var prefix = "";
}

/*** Slides ***/
var currentSlide = 0,
    totalSlides  = $(".tl-item").length - 1;

// Creates the navigation
$(".timeline").after("<div class='tl-nav-wrapper'><ul class='tl-nav'></ul></div><a href='#' class='tl-items-arrow-left'></a><a href='#' class='tl-items-arrow-right'></a>");
$( ".tl-copy" ).wrapInner( "<div class='tl-copy-inner'></div>");

// Cicle through items and creates the nav
$(".tl-item").each(function(i) {
  var year = $(".tl-item:eq(" + i + ")" ).data("year");
  $(".tl-nav").append("<li><div>" + year + "</div></li>");
  
  // Click handlers
  $(".tl-nav li:eq(" + i + ")").click(function() {
    if(!$(".tl-item:eq(" + i + ")" ).hasClass("tl-active")) {
      // Activates the item
      $(".tl-item").removeClass("tl-active");
      $(".tl-item:eq(" + i + ")" ).addClass("tl-active");
      currentSlide = i;

      // Activates the item nav
      $(".tl-nav li").removeClass("tl-active");
      $(".tl-nav li:eq(" + i + ")" ).addClass("tl-active");
    }
  });
});

// Activates the first slide
$(".tl-item:first, .tl-nav li:first").addClass("tl-active");

// Slide's arrows click handlers
$(".tl-items-arrow-left").on("click", function(){
  if(currentSlide > 0) {
    currentSlide--;
  
    // Activates the previous item
    $(".tl-item").removeClass("tl-active");
    $(".tl-item:eq(" + currentSlide +")").addClass("tl-active");
    
    // Activates the previous item nav
    $(".tl-nav li").removeClass("tl-active");
    $(".tl-nav li:eq(" + currentSlide + ")" ).addClass("tl-active");
  }
});

$(".tl-items-arrow-right").on("click", function(){
  if(currentSlide < totalSlides) {
    currentSlide++;
  
    // Activates the next item
    $(".tl-item").removeClass("tl-active");
    $(".tl-item:eq(" + currentSlide +")").addClass("tl-active");
    
    // Activates the next item nav
    $(".tl-nav li").removeClass("tl-active");
    $(".tl-nav li:eq(" + currentSlide + ")" ).addClass("tl-active");
  }
});
  
/*** Nav ***/
// The nav's width
var navWidth = ($(".tl-nav li").outerWidth(true) * $(".tl-nav li").length) + 36;
$(".tl-nav").width(navWidth);

// The nav's arrows
$(".tl-nav-wrapper").append("<a href='#' class='tl-nav-arrow-left'></a><a href='#' class='tl-nav-arrow-right'></a>");

/*** The timeline's height ***/
var vpHeight  = $(window).height();
var tlHeight = vpHeight - $(".tl-nav-wrapper").outerHeight(true) - 26;
$(".tl-wrapper").height(vpHeight);
$(".tl-item").css("max-height", tlHeight);
$(".tl-item").height(tlHeight);

/*** Nav's navigation... ***/
var navTranslation = 0;
var navLimit = (navWidth - $(".tl-nav-wrapper").outerWidth(true) + 20) * -1;

// To the left
$(".tl-nav-arrow-left").on("click", function() {
  if(navTranslation < 0) {
    navTranslation = navTranslation + 86;
    $(".tl-nav").css(prefix + "transform", "translateX(" + navTranslation + "px)");
  }
});

// To the right
$(".tl-nav-arrow-right").on("click", function() {
  if(navTranslation >= navLimit) {
    navTranslation = navTranslation - 86;
    $(".tl-nav").css(prefix + "transform", "translateX(" + navTranslation + "px)");
  }
});
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999px

Console