title: set element opacity with user input in contenteditable div
body: <p>I have a contenteditable <code>div</code> and I want users to be able to set another div's opacity by typing in numbers.</p>
  
  <p><a href="http://jsfiddle.net/w21q35tw/" rel="nofollow">http://jsfiddle.net/w21q35tw/</a></p>
  
  <pre><code>$('#btn').click(function(){
      $('#d').css("opacity", "val('"+$("#set").html()+"')"); //sets opacity - doesn't work
      $('#set').html(val('"+$("#set").html()+"')); //input stays as editable text - works
  });
  </code></pre>
  
  <p>I had no problems with url inputs, but I have no success with neither val or attr in this case. I guess I'm failing to pick up val / attr from html.</p>
  
  <p>How to solve this?</p>