Center absolute parent

<body>
  <div style="position: absolute; left: 50%;">
    <div style="position: relative; left: -50%; border: dotted red 1px;">
      I am some centered shrink-to-fit content! <br />
      tum te tum
    </div>
  </div>
<a href="https://stackoverflow.com/questions/1776915/how-to-center-absolutely-positioned-element-in-div">Source</a>
</body>