raf.js

$('.navbar-brand').css('position', 'fixed').animate({top: 500}, 5000);

(function(e){function o(){t&&(i(o),jQuery.fx.tick())}var t,n=0,r=["webkit","moz"],i=window.requestAnimationFrame,s=window.cancelAnimationFrame;for(;n<r.length&&!i;n++)i=window[r[n]+"RequestAnimationFrame"],s=s||window[r[n]+"CancelAnimationFrame"]||window[r[n]+"CancelRequestAnimationFrame"];i?(window.requestAnimationFrame=i,window.cancelAnimationFrame=s,jQuery.fx.timer=function(e){e()&&jQuery.timers.push(e)&&!t&&(t=!0,o())},jQuery.fx.stop=function(){t=!1}):(window.requestAnimationFrame=function(e,t){var r=(new Date).getTime(),i=Math.max(0,16-(r-n)),s=window.setTimeout(function(){e(r+i)},i);return n=r+i,s},window.cancelAnimationFrame=function(e){clearTimeout(e)})})(jQuery);