jQuery实现拉动页面固定顶部显示且自动消失(火狐)

<!DOCTYPE html> 
<html> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 
<title>回到顶部：哭泣的小丑</title> 
<script src="http://demo.jb51.net/jslib/jquery/jquery-1.6.2.min.js"></script> 
 
<style> 
html, body, div, span, applet, object, iframe,h1, h2, h3, h4, h5, h6, p, blockquote, pre,a, abbr, acronym, address, big, cite, code,del, dfn, em, img, ins, kbd, q, s, samp,small, strike, strong, sub, sup, tt, var,b, u, i, center,dl, dt, dd, ol, ul, li,fieldset, form, label, legend, input,table, caption, tbody, tfoot, thead, tr, th, td,article, aside, canvas, details, embed,figure, figcaption, footer, header, hgroup,menu, nav, output, ruby, section, summary,time, mark, audio, video {margin: 0;padding: 0;border: 0;font-size: 100%;} 
article, aside, details, figcaption, figure,footer, header, hgroup, menu, nav, section {display: block;float:left;}select, input, button,button img, label {vertical-align: middle;}body {font:normal 12px/1.5 "Microsoft Yahei","微软雅黑",Tahoma,Arial,Helvetica,STHeiti; webkit-font-smoothing:antialiased;-moz-font-smoothing: subpixel-antialiased; color:#666;}ol, ul {list-style: none;}blockquote, q {quotes: none;}blockquote:before, blockquote:after,q:before, q:after {content: '';content: none;}table {border-collapse: collapse;border-spacing: 0;}em {font-style: normal}select, input, button, button img, label {vertical-align:middle;}input {font-family:"Microsoft Yahei","微软雅黑";webkit-font-smoothing:antialiased;-moz-font-smoothing: subpixel-antialiased}input, input:focus, button, button:focus, select,textarea, textarea:focus {outline:none; -moz-outline:none; -webkit-outline:none; }input:focus { outline:none; -moz-outline:none; -webkit-outline:none; }textarea {resize:none;}a {color:#666; text-decoration:none;} a:hover {text-decoration:underline;}a:focus {outline:none; -moz-outline:none;-webkit-outline:none;}body {min-width: 960px;} 
</style> 
 
 
<style> 
body{background:#e7e7e7;} 
.clearfix:before, .clearfix:after, .container_24:before, .container_24:after { 
content: '.'; display: block; overflow: hidden; visibility: hidden; font-size: 0; line-height: 0; width: 0; height: 0;} 
.clearfix:after, .container_24:after { clear: both; } 
.Xc_main{width:750px;margin:0 auto;position:relative;} 
.Xc_left{float:left;} 
.Xc_left h1{font-size:24px;padding-top:25px;} 
.Xc_right{float:right;width:600px;} 
.Xc_right .Xc_list{margin:10px 0 10px 0;} 
.Xc_list_top,.Xc_list_main{background:#fff;padding:10px;border:1px solid #ccc;} 
.Xc_list_top{margin-bottom:10px;} 
.Xc_gg{width:90px;height:90px;border:1px solid #ccc;background:#fff;text-align:center;} 
.Xc_bottom{height:650px;background:#fff;padding:10px;border:1px solid #ccc;position:relative;} 
</style> 
 
</head> 
<script> 
$(function () { 
$(".Xc_list_top").css("width",$(".Xc_list_main").width()); 
var resetRightPanelPostion = function () { 
var msie6 = $.browser.msie && $.browser.version == '6.0' && $.browser.version < 7; 
if ($.browser.safari) { 
bodyelem = $("body"); 
} else { 
bodyelem = $("html,body"); 
} 
var bodyTop = bodyelem.scrollTop(); 
var top = $(".Xc_left").offset().top; 
//var t = $("#public_footer").offset().top; 
var t = $("#footerDestinationBox").offset().top; 
//var bottom = $("#footerDestinationBox").offset().top; 
for(var i = 0 ; i < $(".Xc_list .Xc_list_top").length ; i++){ 
if (bodyTop >= top && ((bodyTop + $(".Xc_left").outerHeight()) < t)) { 
if (!msie6) {

if (bodyTop + $(".Xc_gg").outerHeight() >= t) { 
$(".Xc_gg").removeClass('fixed').css({ 
"position": "absolute", 
"top": t - $(".Xc_gg").outerHeight() + "px" 
}); 
} else { 
$(".Xc_gg").css({ 
"position": "fixed", 
"top": 0 
});

} 
} 
} else { 
if (!msie6) { 
$(".Xc_gg").css({ 
"position": "static" 
}); 
} 
}

if(bodyTop>$(".Xc_list").eq(i).offset().top){ 
$(".Xc_list_top").eq(i).css({position:"absolute",top:top-168});

} 
if(bodyTop>$(".Xc_list").eq(i).offset().top){ 
$(".Xc_list_top").eq(i).css({position:"fixed",top:0});

} 
if(bodyTop<=$(".Xc_list").eq(i).offset().top){ 
$(".Xc_list_top").eq(i).css({position:"static",top:0}); 
}

} 
}; 
window.onload = function () { 
if ($(".Xc_gg").length) { 
resetRightPanelPostion(); 
$(window).scroll(function () { 
resetRightPanelPostion(); 
}); 
} 
}

}) 
</script> 
<body> 
 
 
 
 
<h1>小丑</h1> 
Q群:<em style="color:#0069D6;">150508281</em> 
 
 
 
 
 
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 by 脚本之家 @哭泣的小丑 
 
</body> 
</html>

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