title: CSS positioning to fill container: width vs. left/right?
body: <p>Considering:</p>
  
  <ul>
  <li>For elements that are absolutely positioned inside a relatively
  positioned container.</li>
  <li>If you want the element to fill the width of the container.</li>
  <li>The element is also bottom-aligned.</li>
  </ul>
  
  <p><img src="https://i.stack.imgur.com/YG7vP.png" alt="enter image description here"></p>
  
  <p>Is it best for maximum browser compatibility to <a href="http://jsbin.com/ozaziy/1/edit" rel="noreferrer">set a <code>width</code> in pixels</a> for the element, or simply <a href="http://jsbin.com/ozaziy/4/edit" rel="noreferrer">use <code>left</code> and <code>right</code></a>?</p>
  
  <p>Any common bugs to watch out for with either method?</p>
  
  <p>Clearly, using <code>left: 0;</code> and <code>right: 0;</code> would make the code more manageable in cases where the image's width or padding were to change, but are there any downsides where <code>width: 300px</code> would be favorable instead?</p>