<!DOCTYPe html>
<meta charset='utf-8'>
<title>drag and drop – draggable areas – box-shadow</title>
<style>
a {
  display: block;
  height: 200px;
  width: 200px;
  background-color: blue;
  box-shadow: 10px 10px 0 orange;
}
</style>

<p>Try dragging the orange area along the sides of the blue box below. It should <em>not</em> be draggable.</p>

<a href='#' draggable="true" ondragstart="event.dataTransfer.effectAllowed ='copy'"></a>