jQuery(document).ready(function($) {
// set a variable for the anchor link which is the location.hash
var anchorLink = $(window.location.hash);
// test to see if the link is a anchor link, if not the length will have no value, this is done to avoid js errors on non anchor links
if ( anchorLink.length ) {
// set an element as the fixed entity, header in this case and get its height
var offsetSize = $("header").innerHeight();
// fire the animation from the top of the page to the anchor link offsetting by the fixed elements height, the number is the speed of the animation
$("html, body").animate({scrollTop: anchorLink.offset().top - offsetSize }, 500);
}
});