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HTML 

              
                <link href='https://fonts.googleapis.com/css?family=Open+Sans|Maven+Pro:500' rel='stylesheet' type='text/css'>

<header>
  <h1>Scroll Indicator</h1>
  <h3>
    An animated scroll button.
  </h3>
  <a href="http://www.robsawyer.me/blog/2013/09/17/scroll-indicator/">robsawyer.me</a>
</header>


<section class="main">
<a class="arrow-wrap" href="#content">
<span class="arrow"></span>
<!--<span class="hint">scroll</span>-->
</a>
  
  <div class="content" id="content">
    <h1>Content Section</h1>
    <p>
      The purpose of this arrow demo is to indicate that there is further content down the page. While studies have generally shown that users <em>do, in fact,</em> scroll (thus killing the worries about page fold), it still has become somewhat fashionable to indicate scroll intent.
    </p>
    <p>
      A subtle animation triggered after a period of time draws attention to the scroll indicator. Some jQuery hides the indicator after the user begins scrolling.
    </p>
    <h2>
      The CSS
    </h2>
    <pre>
.arrow-wrap {
  position:absolute;
  z-index:1;
  left:50%;
  top:-5em;
  margin-left:-5em;
  background:#111;
  width:10em;
  height:10em;
  padding:4em 2em;
  border-radius:50%;
  font-size:0.5em;
  display:block;
}

.arrow {
  float:left;
  position:relative;
  width: 0px;
  height: 0px;
  border-style: solid;
  border-width: 3em 3em 0 3em;
  border-color: #ffffff transparent transparent transparent;
  -webkit-transform:rotate(360deg)
}

.arrow:after {
  content:'';
  position:absolute;
  top:-3.2em;
  left:-3em;
  width: 0px;
  height: 0px;
  border-style: solid;
  border-width: 3em 3em 0 3em;
  border-color: #111 transparent transparent transparent;
  -webkit-transform:rotate(360deg)
}
    </pre>
    <h2>Animation</h2>
    <p>Be sure to use the correct vendor-prefixes</p>
    <pre>
  @-webkit-keyframes arrows {
    0% { top:0; }
    10% { top:12%; }
    20% { top:0; }
    30% { top:12%; }
    40% { top:-12%; }
    50% { top:12%; }
    60% { top:0; }
    70% { top:12%; }
    80% { top:-12%; }
    90% { top:12%; }
    100% { top:0; }
  }
  
  .arrow-wrap .arrow {
    -webkit-animation: arrows 2.8s 0.4s;
    -webkit-animation-delay: 3s;
  }
    </pre>
    <p>
      Read more at 
  <a href="http://www.robsawyer.me/blog/2013/09/17/scroll-indicator/">robsawyer.me</a>
    </p>
  </div>
  
</section>
!

CSS 

              
                * {
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}

html, body {
  height:100%;
}


body {
  margin:0;
  background:#14b5d1;
  font-size:1.3em;
  color:#333;
  font-family:'Open Sans', sans-serif;
}

section {
  float:left;
  width:100%;
  background:#fff;
  position:relative;
  box-shadow:0 0 5px 0px #333;
}


/* the important styles */

.arrow-wrap {
  position:absolute;
  z-index:1;
  left:50%;
  top:-5em;
  margin-left:-5em;
  background:#111;
  width:10em;
  height:10em;
  padding:4em 2em;
  border-radius:50%;
  font-size:0.5em;
  display:block;
  box-shadow:0px 0px 5px 0px #333;
}

.arrow {
  float:left;
  position:relative;
  width: 0px;
height: 0px;
border-style: solid;
border-width: 3em 3em 0 3em;
border-color: #ffffff transparent transparent transparent;
  -webkit-transform:rotate(360deg)
}

.arrow:after {
  content:'';
  position:absolute;
  top:-3.2em;
  left:-3em;
  width: 0px;
height: 0px;
border-style: solid;
border-width: 3em 3em 0 3em;
border-color: #111 transparent transparent transparent;
  -webkit-transform:rotate(360deg)
}


.hint {
  position:absolute;
  top:0.6em;
  width:100%;
  left:0;
  font-size:2em;
  font-style:italic;
  text-align:center;
  color:#fff;
  opacity:0;
}


.arrow-wrap:hover .hint {
  opacity:1;
}


  @-webkit-keyframes arrows {
    0% { top:0; }
    10% { top:12%; }
    20% { top:0; }
    30% { top:12%; }
    40% { top:-12%; }
    50% { top:12%; }
    60% { top:0; }
    70% { top:12%; }
    80% { top:-12%; }
    90% { top:12%; }
    100% { top:0; }
  }
  
  .arrow-wrap .arrow {
    -webkit-animation: arrows 2.8s 0.4s;
    -webkit-animation-delay: 3s;
  }





/*  this is the unimportant CSS used just to layout the content  */



header {
  float:left;
  width:100%;
  padding:2em 4em;
  color:#fff;
  height:calc(100% - 3em);
}

header h1 {
  margin:0;
}
header h3 {
  margin:0;
  color: #56dcee ;
}

header a {
  color:#56dcee;
  opacity:0.5;
  text-decoration:none;
}

header a:hover {
  color:#333;
  opacity:1;
}


.content {
  float:left;
  width:70%;
  margin:0 15%;
  padding:2em 0;
}

h1 {
  font-family:'Maven Pro', sans-serif;
  font-weight:300;
  font-size:2.4em;
}

h2, h3 {
  font-family:'Maven Pro', sans-serif;
  font-weight:300;
  font-size:1.5em;
  margin-top:2em;
}

pre {
  background:#ededed;
  padding:1em;
}

p {
  color:#555;
  font-size:0.9em;
}

p a {
  color:#14b5d1;
  text-decoration:none;
}
!

JS 

              
                //this is where we apply opacity to the arrow
$(window).scroll( function(){

  //get scroll position
  var topWindow = $(window).scrollTop();
  //multipl by 1.5 so the arrow will become transparent half-way up the page
  var topWindow = topWindow * 1.5;
  
  //get height of window
  var windowHeight = $(window).height();
      
  //set position as percentage of how far the user has scrolled 
  var position = topWindow / windowHeight;
  //invert the percentage
  position = 1 - position;

  //define arrow opacity as based on how far up the page the user has scrolled
  //no scrolling = 1, half-way up the page = 0
  $('.arrow-wrap').css('opacity', position);

});






//Code stolen from css-tricks for smooth scrolling:
$(function() {
  $('a[href*=#]:not([href=#])').click(function() {
    if (location.pathname.replace(/^\//,'') == this.pathname.replace(/^\//,'') && location.hostname == this.hostname) {
      var target = $(this.hash);
      target = target.length ? target : $('[name=' + this.hash.slice(1) +']');
      if (target.length) {
        $('html,body').animate({
          scrollTop: target.offset().top
        }, 1000);
        return false;
      }
    }
  });
});
!
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