.chatvds_menu {
  cursor: pointer;
  width: 180px;
  height: 24px;
  line-height: 22px;
  background-color: #333;
  color: #ffff00;
  font-family: Tahoma, Arial;
  font-size: 13px;
  font-weight: bold;
  text-align: center;
  position: fixed;
  bottom: -1px;
  right: 5px;
  border:1px solid #999;
}
#chatvds
{
  background-image: url("https://i.servimg.com/u/f48/13/58/60/43/mainco13.png");
  z-index: 999;
  position: fixed;
  right:5px;
  bottom: 30px;
  width: 50%;
  height:250px;
  margin: 0px;
  padding: 0px;
  display:none;
  border:1px solid #999;
}
#mes_chatvds, #onl_chatvds {color: #ff0000;}

<!-- BEGIN switch_user_logged_in -->
<div class="chatvds_menu" onclick="chatvds_login();">Chat VĐS [<span id="mes_chatvds">?</span>] - Online [<span id="onl_chatvds">?</span>]</div>
<iframe id="chatvds" src="/chatbox/index.forum?archives=1"></iframe>

<script type="text/javascript">
//<![CDATA[
setTimeout('trangthai_chatvds();',1000);
 
function trangthai_chatvds() {

if(my_getcookie('old_messenger'))
{old_messenger = my_getcookie('old_messenger');}
else
{old_messenger = 0;};

new_messenger = $('#chatvds').contents().find('#chatbox p').length - old_messenger;
if ($('#chatvds').contents().find('#chatbox_option_co').css('display')!='none')
{new_messenger = 'Off';}
else if ((new_messenger < 0)||($('#chatvds').css('display')!='none'))
{new_messenger = '@';};

$('#mes_chatvds').html(new_messenger);

onl = $('#chatvds').contents().find('#chatbox_members ul.online-users li');
$('#onl_chatvds').html(onl.length);
 
setTimeout('trangthai_chatvds();',3000);
}

function chatvds_login(){
$('#chatvds').slideToggle(function(){
old_messenger = $(this).contents().find('#chatbox p').length;
my_setcookie('old_messenger',old_messenger, 1);
if(($(this).contents().find('#chatbox_option_co').css('display')!='none')&&($('#chatvds').css('display')!='none'))
{$(this)[0].contentWindow.CB_disconnect();};
});
}
//]]>
</script>
<!-- END switch_user_logged_in -->