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HTML

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Insecure Resource

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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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HTML 

              
                <h1>Progress bar</h1>
<h2>Javascript using SetInterval to increment the element's width</h2>

<div class="meter cadetblue">
  <span data-progress="12" style="width:0;"></span>
</div>

<div class="meter">
  <span data-progress="35" style="width:0;"></span>
</div>

<div class="meter orange">
  <span data-progress="62" style="width:0;"></span>
</div>
!

CSS 

              
                @import url('https://fonts.googleapis.com/css?family=Roboto')
  
html {
  background-color #efefef
  -webkit-box-sizing border-box
  -moz-box-sizing border-box
  box-sizing border-box
  font-family 'Roboto', sans-serif
  letter-spacing 0.05rem
  word-spacing 0.05rem
}

*, *:before,
*:after {
  -webkit-box-sizing inherit
  -moz-box-sizing inherit
  box-sizing inherit
}

.meter {
  background #ccc
  -webkit-border-radius 25px
  -moz-border-radius 25px
  border-radius 25px
  box-shadow inset 0 -1px 1px rgba(255,255,255,0.3)
  display block
  height 35px
  margin-bottom 10px
  padding 8px
  position relative
  
  > span {
    display block
    height 100%
    border-top-right-radius 8px
    border-bottom-right-radius 8px
    border-top-left-radius 20px
    border-bottom-left-radius 20px
    background-color rgb(43,194,83)
    background-image linear-gradient(to top, rgb(43,194,83) 37%, rgb(84,240,84) 69%)
    box-shadow inset 0 2px 9px rgba(255,255,255,0.3) inset 0 -2px 6px rgba(0,0,0,0.4)
    position relative
    overflow hidden
    transition width 2s ease-out
  }
}

.orange {
  > span {
    background-color orangered
    background-image linear-gradient(to bottom, orange, orangered)
  }
}

.red {
  > span {
    background-color #f0a3a3
    background-image linear-gradient(to bottom, #f0a3a3, #f42323)
  }
}

.cadetblue {
  >span {
    background-color cadetblue
    background-image linear-gradient(to bottom, aqua, dodgerblue)
  }
}
!

JS 

              
                var bars = document.querySelectorAll('.meter > span');
console.clear();

setInterval(function(){
  bars.forEach(function(bar){
    var getWidth = parseFloat(bar.dataset.progress);
    
    for(var i = 0; i < getWidth; i++) {
      bar.style.width = i + '%';
    }
  });
}, 500);
!
999px

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