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// [[Category:Wikipedia scripts]]
$(function(){
'use strict';

$('body').append('<span id="to-bottom">▼ Go to bottom</span>');
var $bottomButton = $('#to-bottom');

$bottomButton.css({
	'color': '#000',
	'position': 'fixed',
	'bottom': '-30px',
	'right': '4px',
	'cursor': 'pointer',
	'transition': 'bottom 0.5s',
	'-webkit-transition': 'bottom 0.5s',
	'user-select': 'none',
	'-webkit-user-select': 'none',
	'-moz-user-select': 'none',
	'-ms-user-select': 'none'
}).click(function(){
	$('html, body').animate({scrollTop:$(document).height()},'slow');
});

$(window).scroll(function(){
	if ($(window).scrollTop() / $(document).height() < 0.8) {
		$bottomButton.css('bottom','4px');
	} else{
		$bottomButton.css('bottom','-30px');
	}
});
});