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HTML

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CSS

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CSS Base

About CSS Base

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JavaScript

About JavaScript Preprocessors

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

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Babel includes JSX processing.

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Packages

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HTML 

              
                <!-- 
Fun and useless fact of the day – Marquee tags can scroll in both directions by nesting them.

Therefore I did the only sensible thing I could think of for this usecase and themed a couple of marquee tags to look like Pong.
-->

<h1>Marquee Pong!</h1>

<!-- To change the speed simply change the scrollamount for both directions! -->
<div class="marquee-wrapper">
  <span class="score score-pl1">4</span>
  <span class="score score-pl2">2</span>
  <marquee direction="down" width="800px" height="600px" behavior="alternate" scrollamount="20" class="marquee-outer">
    <marquee behavior="alternate" scrollamount="20" class="marquee-inner">
      <img src="https://ashleynolan.co.uk/assets/img/blog/santa.png" />
    </marquee>
  </marquee>
</div>
!

CSS 

              
                $mq-margin: 80px;
$pong-border-color: white;
$pong-bg-color: black;

// Define the fonts used in the Pen
@import url(https://fonts.googleapis.com/css?family=Press+Start+2P);

body {
  background-color: #f1f1f1;
  font-family: 'Press Start 2P', cursive;
}

h1 {
  text-transform: uppercase;
  text-align: center;
}

.marquee-wrapper {
  position: relative;
  margin-top: $mq-margin;
}
.marquee-outer {
  position: relative;
  display: block;
  border: solid;
  margin: 0 auto;
  background: $pong-bg-color;
  
  & img {
    width: 60px;
  }
  &:after {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    height: 100%;
    border-left: 1px dashed $pong-border-color;
  }
}
.marquee-inner {
  border-left: 6px solid $pong-border-color;
  border-right: 6px solid $pong-border-color;
  margin: 0 5px;
}

.score {
  position: absolute;
  top: -($mq-margin - 40);
  font-size: 30px;
  z-index: 2;
}
.score-pl1 {
  left: 40%;
}
.score-pl2 {
  right: 40%;
}
!

JS
!
999px

Console