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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

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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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 

              
                <body>
  <div class="banner animate-down-once">
    <div>Beer</div>
    <div>Sleep</div>
    <div>Code</div>
  </div>
</body>
!

CSS 

              
                $font-size: 4rem;

.banner {  // some style for the banner div
  background-color: #333;
  color: #eee;
  font-size: $font-size;
}

.animate-down-once {
	$animation-delay: 3s;    // delay the start from page load
	$animation-length: 9s;  // full time animation will run
  
  div{
    // overlap the divs
    $txt-div-height: 5rem;
    height: $txt-div-height;
    margin-bottom: -$txt-div-height;
    
    opacity: 0;  // start hidden
    text-align: center;
  }

	div:nth-child(1), div:nth-child(2) { 
    animation: slideDownThrough $animation-length linear $animation-delay 1; 
  }
  div:nth-child(2) { animation-delay: ($animation-delay + ($animation-length / 3)); }
  div:nth-child(3) {
		animation: 
      slideDownIn
      ($animation-length / 3)                        // animation length is 1/3 of total run time
      linear                                         // constant timing stucture
      ($animation-delay + ($animation-length / 1.5))  // delay by initial delay plus 2/3 of run time
      1                                              // run once
      forwards;                                      // run once and stop on last frame
  }
}

@keyframes slideDownThrough {
  // slide text down and appear, then slide down and disappear
  0% { opacity: 0; }
  2% { opacity: 0; transform: translateY(-$font-size); }
  5% { opacity: 1; transform: translateY(0px); }
  17% { opacity: 1; transform: translateY(0px); }
	20% { opacity: 0; transform: translateY($font-size); }
	80% { opacity: 0; }
  100% { opacity: 0; }
}

@keyframes slideDownIn {
  // slide text down and appear, freeze on last frame to keep it visible
  0% { opacity: 0; }
  2% { opacity: 0; transform: translateY(-$font-size); }
  17% { opacity: 1; transform: translateY(0px); }
  100% { opacity: 1; transform: translateY(0px); }
}
!

JS
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999px

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