var vtlai_dy=350;
var vtlai_dtime=4;

function vtlai_gettop()
{
try{
if(window.pageYOffset!=undefined)
return window.pageYOffset;
return window.document.body.scrollTop;
}catch(err)
{
try{
return window.document.body.scrollTop;
}catch(err2)
{
return 0;
}
}

}
function vtlai_croll_top()
{

var vtlai_body_obj=window.document.body;
var vtlai_cur_stop=vtlai_gettop();
window.scrollBy (0,-vtlai_dy);
var vtlai_new_stop=vtlai_gettop();
if(vtlai_cur_stop>vtlai_new_stop)
setTimeout("vtlai_croll_top()",vtlai_dtime);
else
document.getElementById("vtlai_scroll_down_img").style.display="block";
return false;
}

function vtlai_croll_down()
{
var vtlai_body_obj=window.document.body;
var vtlai_cur_stop=vtlai_gettop();
window.scrollBy (0,vtlai_dy);
var vtlai_new_stop=vtlai_gettop();
if(vtlai_cur_stop<vtlai_new_stop)
setTimeout("vtlai_croll_down()",vtlai_dtime);
else
document.getElementById("vtlai_scroll_down_img").style.display="none";
return false;
}

function vtlai_display_scroll_btn()
{
var vtlai_body=window.document.body;
var vtlai_height=vtlai_body.scrollHeight;
var vtlai_top=vtlai_gettop();
//document.getElementById("scroll").innerHTML=vtlai_top "/" vtlai_height;
if(vtlai_top==0)
document.getElementById("vtlai_scroll_up_img").style.display="none";
else
document.getElementById("vtlai_scroll_up_img").style.display="block";
/*
if(vtlai_top>=vtlai_height-vtlai_body.clientHeight)
document.getElementById("vtlai_scroll_down_img").style.display="none";
else
document.getElementById("vtlai_scroll_down_img").style.display="block";
*/
}
setInterval("vtlai_display_scroll_btn()",100);
document.write('<div style="position: fixed; filter: alpha(opacity=40); opacity:0.4; width: 40px; right: 5px; bottom: 35px; -moz-transition: 0.5s ease-in; -webkit-transition: 0.5s ease-in; -o-transition: 0.5s ease-in; transition: 0.5s ease-in;" onmouseover="this.style.opacity=1;this.filters.alpha.opacity=100"onmouseout="this.style.opacity=0.4;this.filters.alpha.opacity=40"><a href="#" onclick="return vtlai_croll_top()"><img border="0" id="vtlai_scroll_up_img" src=" http://i41.servimg.com/u/f41/16/91/68/14/top10.png&quot;&gt;&lt;/a&gt; <br /><br /> <a href="#" onclick="return vtlai_croll_down()"><img border="0" id="vtlai_scroll_down_img" src=" http://i41.servimg.com/u/f41/16/91/68/14/buttom10.png&quot;&gt;&lt;/a&gt;&lt;/div&gt;&lt;/div&gt;&#039;);

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