"

From 2014.igem.org

$(function(){

       // Check the initial Poistion of the Sticky Header
       var stickyHeaderTop = $('#menu').offset().top;

       $(window).scroll(function(){
               if( $(window).scrollTop() > stickyHeaderTop ) {
                       $('#stickyheader').css({position: 'fixed', top: '0px'});
                       $('#random').css('display', 'block');
               } else {
                       $('#stickyheader').css({position: 'static', top: '0px'});
                       $('#random').css('display', 'none');
               }
       });
 });