title: Positioning popup window in middle of the screen without JavaScript
body: <p>I have following HTML and CSS, now I would like to position my popup window in middle of screen in any browser window size. Is this possible without JavaScript?</p>
  
  <p>CSS:</p>
  
  <pre><code>.floating-window {
      z-index: 9999;
      position: absolute;
      width: 200px;
  height: 200px;  
      cursor: default;
      -moz-box-shadow: 1px 1px 1px #888;
      -webkit-box-shadow: 1px 1px 1px #888;
      box-shadow: 1px 1px 1px #888;
  }
  </code></pre>
  
  <p>HTML:</p>
  
  <pre><code>&lt;div class='floating-window box'&gt;&lt;/div&gt;
  </code></pre>