$(function() {
var offsetY = 0;
var time = 500;
$('a[href^=#]').click(function() {
var target = $(this.hash);
if (!target.length) return ;
var targetY = target.offset().top+offsetY;
$('html,body').animate({scrollTop: targetY}, time, 'swing');
window.history.pushState(null, null, this.hash);
return false;
});
});