$(function() {

	var show = false
	var on_top_button = $('<div class="on_top" ><div class="on_top_panel" title="Наверх"><div class="on_top_button"><span class="arrow">&uarr;</span> <span class="label">наверх</span></div></div></div>')	
		
	$('body').append(on_top_button);
	
	$('.on_top_panel', on_top_button).click(function(){
		$.scrollTo( $('body') , 500,  { axis: 'y' } );
	})
	

	
	$(window).scroll(function () { 
		show_or_hide()
	})
	
	function show_or_hide(){
		if( window.pageYOffset > 400){
			if(!show){
				on_top_button.show()
				show = true
			}
		}else{
			if(show){
				on_top_button.hide()
				show = false
			}
		}
	}
	
	function mini_or_normal_width(){
		if( $(window).width() < 1330 ){ 
			on_top_button.addClass('mini')
		}else{                          
			on_top_button.removeClass('mini')
		}
	}
	
	$(window).resize(function() {
  	mini_or_normal_width()
	});
	
	mini_or_normal_width()

	show_or_hide()
	
});