Smooth animate/scroll to snippet

smoothScroll.js

$(".scroll").click(function(event){
    event.preventDefault();
    //calculate destination place
    var dest=0;
    if($(this.hash).offset().top > $(document).height()-$(window).height()){
        dest=$(document).height()-$(window).height();
    }else{
        dest=$(this.hash).offset().top;
    }
    //go to destination
    $('html,body').animate({scrollTop:dest}, 1000,'swing');
});