Use to Brighten Target Image as User Scrolls Down Target Content

transition.js

$(document).ready(function(){
	var content = $('#index-content-well'); 
	var image = $('#lead-image');
	content.on('scroll', function(){
		var total_height = content.get(0).scrollHeight - content.height(); 
		var position = Math.abs(Math.round((content.scrollTop() / total_height) * 100) - 100); 
		var value = 'grayscale(' + position +'%)'; 
		image.css('-webkit-filter', value);
		image.css('-moz-filter', value); 
		image.css('filter', value);
	}); 
});