var calunits = "px";
var bouncelimit = 20; // must be divisible by 5
var crossobj;
var timer;

function initbox(id){
	crossobj = document.getElementById(id).style;
	  var middleScreen = 0;
  if( typeof( window.innerWidth ) == 'number' ) { middleScreen = window.innerWidth; } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) { middleScreen = document.documentElement.clientWidth;} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) { middleScreen = document.body.clientWidth; }
	if(middleScreen<863) middleScreen=863;
	middleScreen=middleScreen/2;
 	crossobjWidth=parseFloat(crossobj.width)/2;
 	crossobjLeft=middleScreen-crossobjWidth-100;
	crossobj.left=crossobjLeft+"px";
	var scroll_top = getPageY();
	crossobj.top = (scroll_top - 250) + calunits;
	crossobj.display = "";
	setTimeout("dropin()",50);
}

function dropin() {
	var scroll_top = getPageY();
	if (parseInt(crossobj.top) < 50 + scroll_top){
	    crossobj.top = (parseInt(crossobj.top) + 40) + calunits;
	    setTimeout("dropin()",50);
	}
}

function bouncein(){
	crossobj.top = (parseInt(crossobj.top) - bouncelimit) + calunits;
	if (bouncelimit < 0)
		bouncelimit += 5;
		bouncelimit = bouncelimit * -1;
	if (bouncelimit == 0)
		clearInterval(timer);
}

function getPageY() {
	if (window.pageYOffset)
		var scroll_top = window.pageYOffset;
	else if (document.documentElement.scrollTop)
		var scroll_top = document.documentElement.scrollTop;
	else
		var scroll_top = document.body.scrollTop;
	return scroll_top;
}

function hide(){
	document.getElementById('dropin').style.display = 'none';
}