title: Stellar.js issue with position
body: <p>I'm trying to use Stellar.js to do a parallax effect, but the data-stellar-ratio="" tag is getting my elements out of position. I have this codes:</p>
  
  <pre><code>&lt;div class="slider" id="yours" data-slide="3" data-stellar-background-ratio="0.5"&gt;
  &lt;div class="container"&gt;
  &lt;div class="outer-ring" data-stellar-ratio="0.6"&gt;
  &lt;div class="inner-ring" data-stellar-ratio="-0.6" data-stellar-vertical-offset="0"&gt;
  &lt;div class="core" data-stellar-ratio="-0.3" data-stellar-vertical-offset="0"&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;
  </code></pre>
  
  <p>with these css:</p>
  
  <pre><code>.outer-ring {
      width: 635px;
      height: 635px;
      background: url(../img/conheca/wheel-1.png) no-repeat;
      position: absolute;
      top: 50%;
      margin-top: -317px;
      left: 50%;
      margin-left: -317px;
  }
  
  .inner-ring {
      width: 478px;
      height: 478px;
      background: url(../img/conheca/wheel-2.png) no-repeat;
      position: relative;
      margin: 0px auto;
  }
  
  .core {
      width: 360px;
      height: 360px;
      background: url(../img/conheca/wheel-3.png) no-repeat;
      position: relative;
      margin: 0px auto;
  }
  </code></pre>
  
  <p>When Stellar "data-ratio" is not in the tags, it fits well, but when i put this parameter it changes the "top" of .inner-ring and .core.</p>
  
  <p>I had an issue like this with horizontal positioning, the .container div has "margin: 0 auto" and children elements was getting off the div while it have "position: relative", but i chopped off the "margin" piece of code in the Stellar script and it worked.</p>
  
  <p>Sorry if i was a little confuse, but this thing is driving me insane, since the tutorial i've been following (http://webdesign.tutsplus.com/tutorials/complete-websites/create-a-parallax-scrolling-website-using-stellar-js/) doesn't mention this and neither the Stellar.js site. Thanks.                                                                                                                                                                                                                                                                                                                                                                                                                                                </p>