https://zt-rada.gov.ua/js/ku_button_up_and_down.js

1(function ( $ ) {
2
3		var $this = $("body");
4
5		var sheet = document.createElement('style');
6		sheet.innerHTML  = '#button_up_down{ border:none; width:50px;height:50px;background-color: transparent;background-image: none;position:fixed;bottom:0px;right:0px;text-decoration:none;color: #111;z-index: 100;padding: 10px;-webkit-transition: filter 0.2s linear 0s;-moz-transition: filter 0.2s linear 0s;-o-transition: filter 0.2s linear 0s;transition: filter 0.2s linear 0s;animation: turn_down_up_start 1s linear 0s 1 normal;-webkit-animation: turn_down_up_start 1s linear 0s 1 normal;-o-animation: turn_down_up_start 1s linear 0s 1 normal;-moz-animation: turn_down_up_start 1s linear 0s 1 normal;}';
7		sheet.innerHTML += '#button_up_down::before{font: normal normal normal 30px/1 FontAwesome;content: "\\f078";}';
8		sheet.innerHTML += '#button_up_down:hover{text-decoration:none;outline: none;filter: invert(0.5);-webkit-filter: invert(0.5);-moz-filter: invert(0.5);-o-filter: invert(0.5);-ms-filter: invert(0.5);}';
9		sheet.innerHTML += '#button_up_down.turn_up{animation: turn_down_up 0.5s linear 0s 1 normal;-webkit-animation: turn_down_up 0.5s linear 0s 1 normal;-o-animation: turn_down_up 0.5s linear 0s 1 normal;-moz-animation: turn_down_up 0.5s linear 0s 1 normal;}';
10		sheet.innerHTML += '#button_up_down.turn_up:before{font: normal normal normal 30px/1 FontAwesome;content: "\\f078";}';
11		sheet.innerHTML += '#button_up_down.turn_down{animation: turn_down_up 0.5s linear 0s 1 normal;-webkit-animation: turn_down_up 0.5s linear 0s 1 normal;-o-animation: turn_down_up 0.5s linear 0s 1 normal;-moz-animation: turn_down_up 0.5s linear 0s 1 normal;}';
12		sheet.innerHTML += '#button_up_down.turn_up:before{font: normal normal normal 30px/1 FontAwesome;content: "\\f077";}';
13		sheet.innerHTML += '@keyframes turn_down_up{from{-moz-transform: rotate(180deg);-ms-transform: rotate(180deg);-webkit-transform: rotate(180deg);-o-transform: rotate(180deg);transform: rotate(180deg);}to {-moz-transform: rotate(0deg);-ms-transform: rotate(0deg);-webkit-transform: rotate(0deg);-o-transform: rotate(0deg); transform: rotate(0deg);}}';
14		sheet.innerHTML += '@-webkit-keyframes turn_down_up{from{-moz-transform: rotate(180deg);-ms-transform: rotate(180deg);-webkit-transform: rotate(180deg);-o-transform: rotate(180deg);transform: rotate(180deg);}to {-moz-transform: rotate(0deg);-ms-transform: rotate(0deg);-webkit-transform: rotate(0deg);-o-transform: rotate(0deg); transform: rotate(0deg);}}';
15		sheet.innerHTML += '@-moz-keyframes turn_down_up{from{-moz-transform: rotate(180deg);-ms-transform: rotate(180deg);-webkit-transform: rotate(180deg);-o-transform: rotate(180deg);transform: rotate(180deg);}to {-moz-transform: rotate(0deg);-ms-transform: rotate(0deg);-webkit-transform: rotate(0deg);-o-transform: rotate(0deg); transform: rotate(0deg);}}';
16		sheet.innerHTML += '@-o-keyframes turn_down_up{from{-moz-transform: rotate(180deg);-ms-transform: rotate(180deg);-webkit-transform: rotate(180deg);-o-transform: rotate(180deg);transform: rotate(180deg);}to {-moz-transform: rotate(0deg);-ms-transform: rotate(0deg);-webkit-transform: rotate(0deg);-o-transform: rotate(0deg); transform: rotate(0deg);}}';
17		sheet.innerHTML += '@keyframes turn_down_up_start{from{opacity:0;}to {opacity:1;}}';
18		sheet.innerHTML += '@-webkit-keyframes turn_down_up_start{from{opacity:0;}to {opacity:1;}}';
19		sheet.innerHTML += '@-moz-keyframes turn_down_up_start{from{opacity:0;}to {opacity:1;}}';
20		sheet.innerHTML += '@-o-keyframes turn_down_up_start{from{opacity:0;}to {opacity:1;}}';
21
22		document.body.appendChild(sheet);
23
24		$("body").append('<a href="#" id="button_up_down"> </a>');
25
26		var fn_scroll = function(){
27			var a = $("#button_up_down").attr("a");
28			if( typeof a == "undefined" || a == '0' ){
29				if( $(window).scrollTop() > 500 ){
30					if( $("#button_up_down").attr("class") != "turn_up" ){
31						$("#button_up_down").remove();
32						$this.append('<a href="#" id="button_up_down" class="turn_up"> </a>');
33						$("#button_up_down").click(fn);
34						}
35					}
36				else {
37					if( $("#button_up_down").attr("class") != "turn_down" ){
38						$("#button_up_down").remove();
39						$this.append('<a href="#" id="button_up_down" class="turn_down"> </a>');
40						$("#button_up_down").click(fn);
41						}
42					}
43				}
44			}
45
46		var o = 0;
47		var fn_set_o = function(){
48			if( $("h1").length > 0 || $("footer").length > 0 ){
49				o = $("h1").length > 0?$("h1").offset():$("footer").offset();
50				o = o.top - parseInt($("body").css("padding-top"));
51				}
52			else{
53				o = $(window).height();
54				}
55			}
56
57		var fn = function(){
58			fn_set_o();
59			$("#button_up_down").attr("a",1);
60			if( $("#button_up_down").attr("class") == "turn_up" ){
61				$("html, body").animate({ scrollTop: 0 }, 500,function(){
62					$("#button_up_down").attr("a",0);
63					fn_scroll();
64					});
65				}
66			else{
67				$("html, body").animate({ scrollTop: o }, 500,function(){
68					$("#button_up_down").attr("a",0);
69					fn_scroll();
70					});
71				}
72			return false;

73			}
74
75		$("#button_up_down").attr("a",0);
76		$("#button_up_down").click(fn);
77		$(window).scroll(fn_scroll);
78
79}( jQuery ));