$(document).ready(function() {
	$("ul#header_navi li a img").rollover();
	$("div#sidebar_contactus a img").rollover();
	$("div.sidebar").floatingWidget();
});	
(function ($) {
	$.fn.floatingWidget = function () {
		return this.each(function () {
			var $this			  = $(this),
				$parent 		  = $this.offsetParent(),
				$window 		  = $(window),
				top 			  = $this.offset().top - parseFloat($this.css('marginTop').replace(/auto/, 0)),
				bottom			  = $parent.offset().top + $parent.height() - $this.outerHeight(true),
				floatingClass	  = 'floating',
				pinnedBottomClass = 'pinned-bottom';
			if ($parent.height() > $this.outerHeight(true)) {
				$window.scroll(function () {
					var y = $window.scrollTop();
					if (y > top) {
						$this.addClass(floatingClass);
						if (y > bottom) {
							$this.removeClass(floatingClass).addClass(pinnedBottomClass);
						} else {
							$this.removeClass(pinnedBottomClass);
						}
					} else {
						$this.removeClass(floatingClass);
					}
				});
			}
		});
	};
})(jQuery);