jQuery.fn.topLink = function(settings) {  

settings = jQuery.extend({  

min: 1,  

fadeSpeed: 200,  

ieOffset: 50  

}, settings);  

return this.each(function() {  

//listen for scroll  

var el = $(this);  

el.css('display','none'); //in case the user forgot  

$(window).scroll(function() {  

if(!jQuery.support.hrefNormalized) {  

el.css({  

'position': 'absolute',  

'top': $(window).scrollTop() + $(window).height() - settings.ieOffset  

});  

}  

if($(window).scrollTop() >= settings.min)  

{  

el.fadeIn(settings.fadeSpeed);  

}  

else 

{  

el.fadeOut(settings.fadeSpeed);  

}  

});  

});  

};  

$(document).ready(function() {  

//$('#top-link').topLink({  

//min:800,  

//fadeSpeed: 500  

//});  

//smoothscroll  

$('#back_top').click(function(e) {  

e.preventDefault();  

$.scrollTo(0,300);  

});  

});