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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="container">
  <div class="inner-content">
    <div class="box box_1"><h2>My title</h2><p>Completely maintain tactical collaboration and idea-sharing whereas technically sound models. Continually exploit granular innovation rather than empowered action items.</p><footer></footer></div>
    <div class="box box_2"><h2>My title</h2><p>Completely maintain tactical collaboration and idea-sharing whereas technically sound models. Continually exploit granular innovation rather than empowered action items.</p><footer></footer></div>
  <div class="box box_3"><h2>My title</h2><p>Completely maintain tactical collaboration and idea-sharing whereas technically sound models. Continually exploit granular innovation rather than empowered action items.</p><footer></footer></div>
  <div class="box box_4"><h2>My title</h2><p>Completely maintain tactical collaboration and idea-sharing whereas technically sound models. Continually exploit granular innovation rather than empowered action items.</p><footer></footer></div>
  </div>
</div>
!

CSS 

              
                /* The logic is quite simple : have a fixed height container with display:flex property. Blocks inside have lower heights. Odd and even are self-aligned with flex-start or flex-end properties */

html{
  margin:0;
  padding:0;
  width:100%;
  height:100%;
}
body{
  width:100%;
  height:100%;
  font-family:Arial, sans-serif;
  font-size:16px;
  line-height:30px;
  padding:20px;
  margin:0;
}
*{
  -webkit-box-sizing: border-box; 
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
h2{
  margin: 0;
  padding: 10px; 0
  text-align: center;
  text-transform: uppercase;
  letter-spacing: 15px;
  font-size:18px
}
.container{
  min-height: 1500px;
  display:flex;
  justify-content:center;
  align-items:center;
}
.inner-content{
    display:flex;
    justify-content:center;
    align-items:center;
    width:1000px;
    height:600px;
}
.box{
    height:400px;
    width:250px;
    background-color:#fff;
    display:flex;
    justify-content:flex-around;
    flex-direction:column;
  -webkit-box-shadow: 5px 5px 15px 5px rgba(0,0,0,0.42);box-shadow: 5px 3px 12px 5px rgba(0,0,0,0.1);
}
.box p{
    padding:20px;
    flex:1;
}
footer{
    -ms-flex-item-align: end;
    align-content: flex-end;
    background-color:#000;
    height:30px;
    display: block;
    position:relative
}
.box_1, .box_3{
    -ms-flex-item-align: end;
    align-self: flex-end;
    opacity: 0;
    -webkit-transform: translateY(-100px);
    -ms-transform: translateY(-100px);
    transform: translateY(-100px);
    overflow: hidden;
    -webkit-transition: opacity 0.5s,-webkit-transform 0.7s;
    transition: opacity 0.5s,-webkit-transform 0.7s;
    -o-transition: opacity 0.5s,transform 0.7s;
    transition: opacity 0.5s,transform 0.7s;
    transition: opacity 0.5s,transform 0.7s,-webkit-transform 0.7s;
    margin-bottom: 20px;
}
.box_1.animated, .box_3.animated {
    opacity: 1;
    -webkit-transform: translateY(0px);
    -ms-transform: translateY(0px);
    transform: translateY(0px);
}


.box_2,.box_4{
    background-color:#eee;
    -ms-flex-item-align: start;
    align-self: flex-start;  
    opacity: 0;
    -webkit-transform: translateY(100px);
    -ms-transform: translateY(100px);
    transform: translateY(100px);
    overflow: hidden;
    -webkit-transition: opacity 0.5s,-webkit-transform 0.7s;
    transition: opacity 0.5s,-webkit-transform 0.7s;
    -o-transition: opacity 0.5s,transform 0.7s;
    transition: opacity 0.5s,transform 0.7s;
    transition: opacity 0.5s,transform 0.7s,-webkit-transform 0.7s;
    margin-bottom: 20px;

}
.box_2.animated, .box_4.animated{
    opacity: 1;
    -webkit-transform: translateY(0px);
    -ms-transform: translateY(0px);
    transform: translateY(0px);
}
!

JS 

              
                var $animation_elements = $('.box');
var $window = $(window);

function check_if_in_view() {
  var window_height = $window.height();
  var window_top_position = $window.scrollTop();
  var window_bottom_position = (window_top_position + window_height);
 
  $.each($animation_elements, function() {
    var $element = $(this);
    var element_height = $element.outerHeight();
    var element_top_position = $element.offset().top;
    var element_bottom_position = (element_top_position + element_height);
 
   
    if ((element_bottom_position >= window_top_position) &&
        (element_top_position <= window_bottom_position)) {
      $element.addClass('animated');
    } else {
      $element.removeClass('animated');
    }
  });
}

$window.on('scroll resize', check_if_in_view);
$window.trigger('scroll');
!
999px

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