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HTML

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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

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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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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML 

              
                <div class="wrapper">
  <div class="content">
    <h1>Fade away text</h1>

    <p>Hover over me to reveal the rest. Lorem ipsum dolor sit amet, consectetur adipisicing elit. Tempora doloremque facere quis, molestias dicta! Quidem ullam, dolore assumenda, iste laborum debitis inventore sequi magnam eos tempore recusandae laudantium dignissimos voluptates.Perferendis illo eius provident rem consequatur, sequi eos nulla sit nihil alias sapiente, dolorum natus laboriosam harum consectetur maxime facilis, ipsam commodi.</p>
  </div>
</div>
!

CSS 

              
                @mixin fadeText($text-color, $direction : top, $offset : 2em, $transition: 0.5s ease-out) {  
  // text-color : dark
  $color: #fff;

  // direction : top
  $deg: 180deg;
  $pos: bottom;
  
  @if($text-color == 'light') {
    $color: #000;
    mix-blend-mode: screen;
  } @else {
    mix-blend-mode: multiply;
  }
  
  @if($direction == 'left') {
    $deg: 90deg;
    $pos: right;
  } @elseif ($direction == 'right') {
    $deg: -90deg;
    $pos: left;
  } @elseif ($direction == 'bottom') {
    $deg: 0deg;
    $pos: top;
  }
  
  position: relative;

  &::after {
    background: linear-gradient($deg, transparent, $color $offset) no-repeat $pos center / 100% 100%;
    
    content: '';
    position: absolute;
    top: 0; right: 0; bottom: 0; left: 0;
    pointer-events: none;
    transition: $transition;
  }
  
  &:hover::after {
    @if($direction == 'left' or $direction == 'right') {
      background-size: 0% 100%;  
    } @else {
      background-size: 100% 0%;
    }
  }
  
}

// Your text color should have good contrast (either very light or very dark, with the appropriate option passed above) or the entire block will start turning transparent

p {
  color: #fff;
  @supports(mix-blend-mode: screen){
     @include fadeText(light, top, 3rem);
  } 
}

/* Pen styling */
// This was on <body> but then it mysteriously broke on Chrome
.wrapper {
  background: #222 url(https://source.unsplash.com/yNGQ830uFB4/1600x900) 50% 50% / cover;
  display: flex;
  align-items: center;
  font: 18px/1.5 'Roboto', sans-serif;
  justify-content: center;
  min-height: 100vh;
  position: relative;
  
  &::before {
    background: #222;
    content: '';
    position: absolute;
    top: 0; right: 0; bottom: 0; left: 0;
    opacity: 0.5;
  }
}

h1 {
  font-size: 32px;
  font-weight: 300;
}

.content {
  color: #fff;
  max-width: 600px;
  text-align: center;
  position: relative;
}
!

JS
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999px

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