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HTML

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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.

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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

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CSS

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

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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).

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="page">

  <div class="container">
    <div class="carousel">
      <ul class="carousel-pagination">

        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>
        <li class="carousel-bullet"></li>

      </ul>

      <div class="carousel-container">
        <p class="carouselPara">

          This book is here to help you get your job done. In general, if this book includes code examples, you may use the code in your programs and documentation. You do not need to contact us for permission unless you’re reproducing a significant portion of
          the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing a CD-ROM of examples from O’Reilly books does require permission. Answering a question by citing this
          book and quoting example code does not require permission. Incorporating a significant amount of ex‐ ample code from this book into your product’s documentation does require permission. We appreciate, but do not require, attribution. An attribution
          usually includes the title, author, publisher, and ISBN. For example: “Developing Backbone.js Applications by Adnan Osmani (O’Reilly). Copyright 2013 Addy Osmani, 978-1-449-32825-2.” If you feel your use of code examples falls outside fair use
          or the permission given above, feel free to contact us at [email protected]. Safari® Books Online Safari Books Online (www.safaribooksonline.com) is an on-demand digital library that delivers expert content in both book and video form
          from the world’s leading authors in technology and business. Technology professionals, software developers, web designers, and business and crea‐ tive professionals use Safari Books Online as their primary resource for research, prob‐ lem solving,
          learning, and certification training. Safari Books Online offers a range of product mixes and pricing programs for organi‐ zations, government agencies, and individuals. Subscribers have access to thousands of books, training videos, and prepublication
          manuscripts in one fully searchable database from publishers like O’Reilly Media, Prentice Hall Professional, Addison-Wesley Pro‐ fessional, Microsoft Press, Sams, Que, Peachpit Press, Focal Press, Cisco Press, John Wiley & Sons, Syngress, Morgan
          Kaufmann, IBM Redbooks, Packt, Adobe Press, FT Press, Apress, Manning, New Riders, McGraw-Hill, Jones & Bartlett, Course Technology, and dozens more. For more information about Safari Books Online, please visit us online. </p>
      </div>

    </div>
  </div>
</div>
!

CSS 

              
                body {
  background: #FFF;
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 100%;
  font: inherit;
  vertical-align: baseline;
  overflow-y: scroll;
  overflow-x: hidden;
  min-height: 600px;
}
.page {
  margin-top: 50px;
  width: 700px;
  height: 300px;
}

.container {
  width: 700px;
  height: 100%;
  margin: 0 auto;
  box-shadow: 0 16px 18px -10px rgba(0, 0, 0, 0.5);
  -moz-box-shadow: 0 16px 18px -10px rgba(0, 0, 0, 0.5);
  -webkit-box-shadow: 0 16px 18px -10px rgba(0, 0, 0, 0.5);
  -o-box-shadow: 0 16px 18px -10px rgba(0, 0, 0, 0.5);
  border-radius: 0px 0px 10px 10px;
}

.carousel {
  position: relative;
  overflow: hidden;
  width: 700px;
}

.carousel-pagination {
  list-style: none;
  position: absolute;
  left: 0;
  right: 0;
  width: 700px;
  height: 25px;
  padding: 10px 0px 0px 0px;
  margin: 0 auto;
  text-align: center;
  z-index: 10;
  background-color: #F6F6F6;
}

.carousel-bullet {
  display: inline-flex;
  width: 10px;
  height: 10px;
  background-color: #B7B7B7;
  cursor: pointer;
  border-radius: 50%;
  opacity: 0.5;
  
/*   transition-property: transform, opacity, background-color; */
/*   transition-duration: 0.3s; */
}

/* .carousel-bullet:hover {
  -webkit-transform: scale(1.1);
  transform: scale(1.1);
} */

/* .carousel-bullet.active-bullet, .carousel-bullet.active-bullet:hover {
  opacity: 1;
  -webkit-transform: scale(1.1);
  transform: scale(1.1);
  background-color: #324892;
  cursor: default;
} */
.carousel-container {
  background-color: #CCC;
  margin-top: 50px;
  width: 700px;
  height: 300px;
/*   transition: transform 0.3s cubic-bezier(.694, .0482, .335, 1); */
  overflow-y: hidden;
  overflow-x: scroll;
}

p {
  padding: 10px;
  width: 200%;
}
!

JS 

              
                
var container = document.querySelector(".carousel-container");
var bulletElements = document.querySelectorAll(".carousel-bullet");

var scrollArea = container.scrollWidth - container.offsetWidth;
var length = bulletElements.length;
var bullets = [];

var requestId = null;

// Prevent Chrome from rasterizing at scale of 1
// https://greensock.com/will-change
TweenLite.set(bulletElements, {
  force3D: true
});

for (var i = 0; i < length; i++) {
  var bullet = createBullet(bulletElements[i], i);
  bullets.push(bullet);
}

container.addEventListener("scroll", requestScrollUpdate);

updateScroll();

// Throttle scroll events to animation frames
function requestScrollUpdate() {
  if (!requestId) {
    requestId = requestAnimationFrame(updateScroll);
  }
}

function updateScroll() {
  
  var ratio = container.scrollLeft / scrollArea;
  var cursor = Math.floor((length - 1) * ratio);
  
  for (var i = 0; i < length; i++) {
    bullets[i].updateProgress(cursor);
  }  
  
  requestId = null;
}

function createBullet(element, index) {
    
  var animation = new TimelineMax({ paused: true })
    .to(element, 1, { scale: 2, backgroundColor: "pink" })
    .to(element, 1, { scale: 3, backgroundColor: "red" })
  
  var bullet = {
    element: element,
    index: index,
    animation: animation,
    updateProgress: updateProgress
  };
    
  function updateProgress(cursor) {
    
    // Use a small progress value here instead of 0
    // to work around will-change issue in Chrome
    var progress = 0.0001;
    
    if (cursor === index) {
      progress = 1;
    } else if (cursor === index - 1 || cursor === index + 1) {
      progress = 0.5;
    }
    
    if (animation.progress() !== progress) {
      TweenLite.to(animation, 0.25, { progress: progress });
    }   
  }
  
  return bullet;
}
!
999px

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