var scrollTop;
var maxTop;
var bottom;

$(function(){
	if($('#navi').length){
		maxTop = $('#navi').offset().top;
		$('#wrapper').css({
			position: 'relative',
			top: 0,
			left: 0
		});
		$('#navi').css({
			position: 'absolute',
			top: $('#navi').offset().top + 'px',
			left: 15
		});
		var timer = setInterval(elevate, 100);
	}
});

function elevate(){
	bottom = $(document).height() - $('#navi').outerHeight() - $('#footer').outerHeight();
	if ( scrollTop != $(document).scrollTop()) {
		scrollTop = $(document).scrollTop();
		destination = ( scrollTop > maxTop ) ? scrollTop : maxTop;
		destination = (destination < bottom) ? destination : bottom;
		$('#navi').queue([]).animate({ top: destination + 'px' }, 500);
	}
}