function setCss(){var a=[];a.push(".back_to_top{display:none;width:35px;height:35px;overflow:hidden;left:50%;margin-left: 592px; position:fixed; z-index:12; bottom:30px;_position:absolute;_top:expression(eval(document.documentElement.scrollTop+document.documentElement.clientHeight-134));}\n");a.push(".back_to_top a{display:inline-block;width:35px;height:35px;overflow:hidden;background: url(/js/top.png) 0px 0px no-repeat;}\n");a.push(".back_to_top a:hover{background-position:-35px 0px}");try{var b=document.createStyleSheet();b.cssText=a.join("");}catch(c){var b=document.createElement("style");b.type="text/css";b.textContent=a.join("");document.getElementsByTagName("HEAD").item(0).appendChild(b);}}function createLink(){var a=document.createElement("div");a.id="JS_back_to_top";a.className="back_to_top";a.innerHTML='<a href="#" title="还回顶部"></a>';document.body.appendChild(a);}function GetPageScroll(){var b,a;if(window.pageYOffset){a=window.pageYOffset;b=window.pageXOffset;}else{if(document.documentElement&&document.documentElement.scrollTop){a=document.documentElement.scrollTop;b=document.documentElement.scrollLeft;}else{if(document.body){a=document.body.scrollTop;b=document.body.scrollLeft;}}}return{x:b,y:a};}if(window.attachEvent){window.attachEvent("onscroll",backToTop);}else{window.addEventListener("scroll",backToTop,false);}function backToTop(){if(GetPageScroll().y>300){document.getElementById("JS_back_to_top").style.display="block";}else{document.getElementById("JS_back_to_top").style.display="none";}}createLink();setCss();