new FLEXBOX 2013 (http://dev.w3.org/csswg/css-flexbox/#box-model)

The old 2009 syntax has surprisingly good browser "support": Chrome, Firefox 2+, Safari 3.1+... Pretty much everything except IE 9- and Opera anything. I say "support" because the actual implementations were partial and differed a bit (hence the re-write). Despite more support, it's not smart to be using the older syntax. The old spec is gone with the wind. Browsers might drop support for the old syntax in the future. At the least, it's very likely the new syntax is easier to understand and will be implemented more deeply and more consistently. Browsers that don't yet support Flexbox will implement the new spec, which is in "CR" (Candidate Recommendation) status.

by Leo Lanese

HTML

<div class="grid">
  <div class="col fluid">
    
    <h2>Fluid</h2>
  
		<p>Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo.</p>	
  
  </div>
  <div class="col fixed">
  
    <h2>Fixed</h2>
    
		<p>Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo.</p>	
  
  </div>
  <div class="col fluid">
    
    <h2>Fluid</h2>
  
		<p>Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo.</p>	
    
  </div>
</div>

CSS

.grid {
  /*  new flexbox  */
  display: -webkit-flex;
  display: flex;
}
.col {
	background: #ccc;
  padding: 30px;
}

.fixed {
  background: red;
  width: 200px;
}

JavaScript

<!--
code borrowed from @chriscoyier
-->