var background = {

set:function()
{
  var windowWidth  = document.body.clientWidth;
  var windowHeight = document.body.clientHeight;

  var left = Math.max(0.5 * (windowWidth  - 900),0);
  var top  = Math.max(0.5 * (windowHeight - 780),0);

  var sunID = document.getElementById('sun');

  if( left > 0 || top > 0 )
  {
    var text = '<img style="position:absolute; left:0px; top:0px; width:500px; height:500px" src="images/sun.jpg">';

    text += '<div style="position:absolute; left:' + (left - 1) + 'px; top:' + (top - 1) + 'px; width:500px; height:782px; background-color:rgb(72,124,218); overflow:hidden"></div>';

    sunID.innerHTML = text;
  }

  sunID.style.width  = windowWidth;
  sunID.style.height = windowHeight;



}
}