title: Value calculation for CSS
body: <p>As a web developer you often run into problems that might be solved very easily if there was something like value calculation.</p>
  
  <p>I've often wondered why it is not possible to do something like this in CSS:</p>
  
  <pre><code>line-height: (height / 2)px;
  </code></pre>
  
  <p>This would solve some problems you run into when you want to vertical align an element, for example. It is difficult to vertical align elements using CSS right now and produces quite some overhead.</p>
  
  <p>You do not need this in cases where you know the fixed height of an element. But as soon as the height is subject to change (longer text, etc.) you are screwed on knowing the total height of an element.</p>
  
  <p>It would be easy to solve this problem using additional JS, but this is out of question for normal websites. So why don't we just add the ability in CSS to refer to current values and work with them?</p>
  
  <p>If you look into questions like this, you know what cases I mean:</p>
  
  <ul>
  <li><a href="https://stackoverflow.com/questions/522928/can-you-do-this-html-layout-without-using-tables">Can you do this html layout without
  using tables</a></li>
  </ul>