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HTML

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Adding Classes

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About the <head>

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CSS

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JavaScript

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HTML 

              
                <!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
  </head>
<body>

<div class="timeline">
  <div class="container left">
    <div class="content">
      <h2>2017</h2>
      <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.</p>
    </div>
  </div>
  <div class="container right">
    <div class="content">
      <h2>2016</h2>
      <p>Lorem ipsum dolor sit amet, quo ei simul congue exerci, ad nec admodum perfecto mnesarchum, vim ea mazim fierent detracto. Ea quis iuvaret expetendis his, te elit voluptua dignissim per, habeo iusto primis ea eam.</p>
    </div>
  </div>
  <div class="container left">
    <div class="content">
      <h2>2015</h2>
      <p>Lorem ipsum dolor sit amet, quo ei simul congue exerci, ad nec admodum perfecto mnesarchum, vim ea mazim fierent detracto. Ea quis iuvaret expetendis his, te elit voluptua dignissim per, habeo iusto primis ea eam.</p>
    </div>
  </div>
  <div class="container right">
    <div class="content">
      <h2>2012</h2>
      <p>Lorem ipsum dolor sit amet, quo ei simul congue exerci, ad nec admodum perfecto mnesarchum, vim ea mazim fierent detracto. Ea quis iuvaret expetendis his, te elit voluptua dignissim per, habeo iusto primis ea eam.</p>
    </div>
  </div>
  <div class="container left">
    <div class="content">
      <h2>2011</h2>
      <p>Lorem ipsum dolor sit amet, quo ei simul congue exerci, ad nec admodum perfecto mnesarchum, vim ea mazim fierent detracto. Ea quis iuvaret expetendis his, te elit voluptua dignissim per, habeo iusto primis ea eam.</p>
    </div>
  </div>
  <div class="container right">
    <div class="content">
      <h2>2007</h2>
      <p>Lorem ipsum dolor sit amet, quo ei simul congue exerci, ad nec admodum perfecto mnesarchum, vim ea mazim fierent detracto. Ea quis iuvaret expetendis his, te elit voluptua dignissim per, habeo iusto primis ea eam.</p>
    </div>
  </div>
</div>

</body>
</html>
!

CSS 

              
                * {
  box-sizing: border-box;
}

body {
  background-color: #474e5d;
  font-family: Helvetica, sans-serif;
}
h2{
  margin: 0 0 10px;
  padding: 0;
}
/* The actual timeline (the vertical ruler) */
.timeline {
  position: relative;
  max-width: 1200px;
  margin: 0 auto;
}

/* The actual timeline (the vertical ruler) */
.timeline::after {
  content: '';
  position: absolute;
  width: 2px;
  background-color: #FFF;
  top: 0;
  bottom: 0;
  left: 50%;
  margin-left: -1px;
}

/* Container around content */
.container {
  padding: 10px 30px;
  position: relative;
  background-color: inherit;
  width: 50%;
}

/* The circles on the timeline */
.container::after {
  content: '';
  position: absolute;
  width: 14px;
  height: 14px;
  right: -9px;
  background-color: #335577;
  border: 2px solid #FFF;
  top: 20px;
  border-radius: 50%;
  z-index: 1;
}

/* Place the container to the left */
.left {
  left: 0;
}

/* Place the container to the right */
.right {
  left: 50%;
}

/* Add arrows to the left container (pointing right) */
.left::before {
  content: " ";
  height: 0;
  position: absolute;
  top: 22px;
  width: 0;
  z-index: 1;
  right: 30px;
  border: medium solid white;
  border-width: 10px 0 10px 10px;
  border-color: transparent transparent transparent white;
}

/* Add arrows to the right container (pointing left) */
.right::before {
  content: " ";
  height: 0;
  position: absolute;
  top: 22px;
  width: 0;
  z-index: 1;
  left: 30px;
  border: medium solid white;
  border-width: 10px 10px 10px 0;
  border-color: transparent white transparent transparent;
}

/* Fix the circle for containers on the right side */
.right::after {
  left: -9px;
}

/* The actual content */
.content {
  padding: 20px;
  background-color: white;
  position: relative;
  border-radius: 6px;
}

/* Media queries - Responsive timeline on screens less than 600px wide */
@media screen and (max-width: 600px) {
  /* Place the timelime to the left */
  .timeline::after {
  left: 17px;
  }
  
  /* Full-width containers */
  .container {
  width: 100%;
  padding-left: 50px;
  padding-right: 20px;
  }
  
  /* Make sure that all arrows are pointing leftwards */
  .container::before {
    top: 20px;
    left: 35px;
    border-width: 10px 15px 10px 0;
    border-color: transparent white transparent transparent;
  }

  /* Make sure all circles are at the same spot */
  .left::after, .right::after {
  left: 8px;
  }
  
  /* Make all right containers behave like the left ones */
  .right {
  left: 0%;
  }
}
!

JS
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999px

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