title: Div not centered from ie8 to ie11
body: <p>An important div in my website has moved from center of the screen to right-bottom when i moved from ie8 to ie11, i tried different things but i couldn't fix it :</p>
  
  <pre><code>.ModalDialog{
      border:1px solid #3C4749;
      background-color:#FFF;
      margin:0 auto 0 auto;
      position:relative;
      display:none;
      min-height:1px;
      top:250px;
      left:450px;
      width: auto;
      max-width: 500px;
      font-size: 12px;
  }
  </code></pre>
  
  <p>How can i have a perfectly centered div horizontally and vertically for ie11 for any screen resolution (or most of them) ?</p>