var initPage = function() {
	initScroll();
}
var initScroll = function() {
	var scroll = document.getElementById('scroll');
	var up = document.getElementById('scroll-up');
	var down = document.getElementById('scroll-down');
	if (scroll && up && down) {

		var y = 0;
		var height = document.getElementById('scroll').clientHeight;
		height = 0 - (height - 400);

		scroll.style.top = y + 'px';

	    down.onclick = function() {
			if ( y > height){
				y = y - 25;
                scroll.style.top = y + 'px';
			}
			return false;
		};

		up.onclick = function() {
			if (y < 0){
			    y = y + 25;
			    scroll.style.top = y + 'px';
			}
			return false;
		};
	}
}

if (window.addEventListener){
	window.addEventListener("load", initPage, false);
} else if (window.attachEvent){
	window.attachEvent("onload", initPage);
}