er box below and drop it. Silver box should turn green.</p>
<div ondragenter="enterElement(event)" ondragover="overElement(event)" ondrop="dataDrop(event)"/>
<pre/>
<script type="application/ecmascript">
var canvas = document.querySelector('canvas'),
c = canvas.getContext('2d');
for(var x = 0; x != 50; x++)
  {c.fillStyle = (x%2 == 0)?'navy':'white';
  c.beginPath();
  c.moveTo(x,x);
  c.lineTo(100-x,x);
  c.lineTo(100-x,100-x);
  c.lineTo(x,100-x);
  c.closePath();
  c.fill();}
data[1] = canvas.toDataURL('