function game_demo()
{
	  var mywin;
	   W = 780
	   H  = 480
	   msdn = "game_demo.html";
	   var myW = W ? W : screen.availWidth;
	   var myH = H ? H : screen.availHeight;
	   mywin = window.open(msdn,"",'width='+myW+',height='+myH+', top=2,left=2,scrollbars=no');
//	   mywin = window.open(msdn,'',"width=770,height=430,top=2,left=2,scrollbars=yes");
	   mywin.resizeTo(myW,myH);
}