//
// scrollchaser.js
//
// 2008.2.4
//
function ScrollChaser(id,int){
var el;
var initTop;
var interval = int;
//
function setting()
{
	el = document.getElementById(id);
	el.style.position = 'relative';
	initTop = el.offsetTop;
	try {
		window.addEventListener('scroll', scrollEvent, false);
	} catch (e) {
		window.attachEvent('onscroll',scrollEvent);
	}
}
function scrollEvent()
{
	var myInt = setInterval(function()
		{
			var cur = (document.body.scrollTop||document.documentElement.scrollTop) /*+60*/;
			var myTop = el.offsetTop;
			var d = cur-myTop;
			if(Math.abs(d)>1) {
				if( cur >= initTop )
				{
					var y = myTop + d/3;
					el.style.top = y+"px";
				} else {
					el.style.top = initTop+"px";
					clearInterval(myInt);
				}
			} else {
				el.style.top = cur+"px";
				clearInterval(myInt);
			}
		},interval);
}
/*
function getTop( args )
{
	var el = args.el;
	var tagName = el.tagName;
	var top = args.top||0;
	if(tagName=='body'||tagName=='BODY')
	{
		return top;
	} else {
		return arguments.callee( { el:el.offsetParent, top:top += el.offsetTop } );
	} 
}
function setPx( num )
{
	return num+'px';
}*/
try {
    window.addEventListener('load', setting, false);
} catch (e) {
    window.attachEvent('onload', setting);
}
}
var sc = new ScrollChaser('pr-space',200);