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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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Vendor Prefixing

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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 

              
                <div class="wrapper">
  <h2>How to make sticky menu stick to wrapper/container.</h2>
</div>
<div class="menu"></div>
!

CSS 

              
                body{
  background: #e3e3e3;
  padding-bottom: 1000px;
}
.wrapper {
  width: 600px;
  min-height: 400px;
  display: block;
  background: #fff;
  margin:100px auto;
  text-align:center;
}
h2 {
  padding:20px 0;
  
}
.menu{
  background: #ccc;
  width:100px;
  height: 200px;
  display: block;
  position: fixed;
  top: 0;
  left: 0;
}
!

JS 

              
                //Start after window load so not messy jumping effect.
// else menu appear top 0 left 0 than jump calculated position
// TODO : If page loads when scrolled way down , menu placed wrong position.So check position for it.

$(window).load(function(){
    
  var container        = $('.wrapper'), // Container Div
      containerPos     = container.offset(), // Container Offset
      containerWidth   = container.width(),//Container Width
      margin           = 10, // Menu Margin to Container
      menu             = $('.menu');
      // Lets Set Menu left location
      menu.css({
        // Menu top position must be container offset top.
        top:containerPos.top,
        // Menu left position Container Width + Container Offset Left + Margin
        left:containerWidth+containerPos.left+margin
      });
      $(window).scroll(function() {
        // Lets calculate bottom corner offset top when menu hit container bottom
        var bottomOffset = container.height()- menu.height();
        // 
        if($(window).scrollTop()>=bottomOffset){
          // When it hits corner we have to determine margin value top of menu.
          var margintop= $(window).scrollTop() - (container.height() - menu.height());
          menu.css({
            marginTop:-margintop
          });
        }else {
          //Dont ask
          menu.css({
            marginTop:0
          });
        }
      });
    
});
!
999px

Console