"

From 2014hs.igem.org

jQuery(document).ready(function() { var offset = 220; var duration = 100; jQuery(window).scroll(function() { if (jQuery(this).scrollTop() > offset) { jQuery('.back-to-top').fadeIn(duration); } else { jQuery('.back-to-top').fadeOut(duration); } });

jQuery('.back-to-top').click(function(event) { event.preventDefault(); jQuery('html, body').animate({scrollTop: 0}, duration); return false; }) });