Dropdown menu appearing behind google map.

[sg552]

Hello everyone,

I have a problem with my page, my drop down menu is appearing behind google map. More info on my page is here: http://smkhutankampong.co.cc/mengenaikami/pelanlokasi.php

Please hover on the "MENGENAI KAMI" top navigation and you will see the dropdown menu is appearing behind the google map.

This is my top navigation html code - menu.inc.php

$topmenu = "<li><a href=\"/\">LAMAN UTAMA</a></li>
            <li><a href=\"tentangkami.php\">MENGENAI KAMI</a>
            <ul style=\"visibility: hidden; margin-top:45px; width:120px; left:174px;\">
            <li  style=\"float:none;\"><a href=\"/mengenaikami/piagam.php\"  style=\"float:none; width:145px;\">Piagam Sekolah</a></li>
            <li style=\"float:none; \"><a href=\"/mengenaikami/visi&misi.php\" style=\"float:none; width:145px;\">Visi & Misi</a></li>
            <li style=\"float:none; \"><a href=\"/mengenaikami/latarbelakang.php\" style=\"float:none; width:145px;\">Latar Belakang</a></li>		
			<li style=\"float:none; \"><a href=\"/mengenaikami/pelanlokasi.php\" style=\"float:none; width:145px;\">Pelan Lokasi</a></li>	
            <li  style=\"float:none;\"><a href=\"#\"  style=\"float:none; width:145px;\">Ajax Navigation</a></li>
            </ul>
            </li>			
            <li><a href=\"/galeri.php\">GALERI FOTO</a></li>
			<li><a href=\"/infopendidikan.php\">INFO PENDIDIKAN</a></li>
			<li><a href=\"/alumni.php\">ALUMNI</a></li>
            <li><a href=\"/hubungi.php\">HUBUNGI KAMI</a></li>";

My top navigation is using php include from menu.inc.php. The dropdown menu is using jQuery.

I'm open to all suggestion. Any help is appreciated. Thanks in advanced. :)