title: Breaking out of string in javaScript css declaration?
body: <p>Sorry for the weak title.</p>
  
  <p>I have some jQuery that is going pretty well, however, I guess I don't know some of the basics. I want to write -wt/2px as the left margin but I don't understand how it's breaking out between string and number - any help?</p>
  
  <p>Here is what we came up with after the answer / (we were over-riding our own css was just one of the problems <a href="http://codepen.io/nouveau/pen/pLACg" rel="nofollow">CODEPEN</a></p>
  
  <p>jQuery</p>
  
  <pre><code>$(document).ready(function(){
  
    var innerH = $('.v-align'),
      ht = innerH.height();
  
    var innerW = $('.h-align'),
      wt = innerW.width();
  
    innerH.css({
      'position':'absolute',
      'top':'50%',
      'margin':-ht/2+'px 0 0 0'
    });
  
    innerW.css({
      'position':'absolute',
      'left':'50%',
      // ?
      'margin': '0 0 0 '+(-wt/2)+'px'
    });
  
  });
  </code></pre>