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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Insecure Resource

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CSS

About CSS Preprocessors

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.

Vendor Prefixing

About 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="bob"></div>
<div class="bob"></div>
<div class="bob"></div>
<div class="bob"></div>
<div class="bob"></div>
!

CSS 

              
                body {
  background: black;
  margin: 0;
  margin-top: 20vh;
}

.bob {
  width: 200px;
  height: 20px;
  background: #333;
  position: relative;
  display: block;
  margin: auto;
  margin-bottom: 10px;
  margin-top: 10px;
}
!

JS 

              
                var items=document.querySelectorAll(".bob");
for(var i=0;i<items.length;i++){
  TweenMax.to(items[i],.5,{x:i%2==0?"+=200":"-=200",opacity:0, delay:.1*i});
}

/* It would be a great thing to add to TweenMax that already handles an array of objects.
If you add this to where you set up your for-loop for multiple tweens, you first check to see if an alternate properties exist.
If it does, flip flop between both properties as you set up your tweens.

I could see a possible new custom property being added like this:
TweenMax.staggerFrom(".bob",.5,{opacity:0,x:"+=200",delay:1,alternate:{x:"-=200"}},.2);

UPDATE: I created a new version of TweenMax to do just this!
https://dl.dropboxusercontent.com/u/1256960/%20Research/JS/TweenMaxAlternate/index.html

Also added a topic on the Greensock Forums
https://greensock.com/forums/topic/12208-alternating-property-direction-with-any-array/
*/
!
999px

Console