I'm making a site and the drop-down menu I've coded doesn't seem to be dropping down. Could anyone help?

 

LINK:

www.mylzh.net

 

HTML:

<div id="nav">
<ul id="jsddm">
 <li><a href="http://mylzh.net/content.php"><!--BACK UP START-->HOME<!--BACK UP END--></a></li>
<li>
<a>COMMUNITY</a>
<ul>
   <li><a href="http://mylzh.net/arcade.php">Arcade</a></li>
   <li><a href="http://mylzh.net/content.php?1015">Guides</a></li>
   <li><a href="http://mylzh.net/content.php?193-Social-Networks">Social Networks</a></li
   <li><a href="http://mylzh.net/content.php?126-lzhwiki">Lzuruha Wiki</a></li>

   <li><a href="http://mylzh.net/content.php?185-Voice-Servers">Voice Servers</a></li>
   <li><a href="http://mylzh.net/content.php?638-Game-Servers">Game Servers</a></li>
</ul>
</li>
<li>
<a>PORTALS</a>
<ul>
   <li><a href="http://mylzh.net/content.php?388-battlefield">Battlefield 3</a></li>
   <th><li><a href="http://mylzh.net/content.php?248-cod_news">Call Of Duty: Modern Warfare 3</a></li>
   <li><a href="http://mylzh.net/content.php?246-starcraft_2_news">StarCraft II: Heart of the Swarm</a></li>
   <li><a href="http://mylzh.net/content.php?249-cs_news">Counter-Strike: Source</a></li>
   <li><a href="http://mylzh.net/content.php?341-d3_news">Diablo III</a></li>
   <li><a href="http://mylzh.net/content.php?252-lol_news">League Of Legends</a></li>
   <li><a href="http://mylzh.net/content.php?387-minecraft_news">MineCraft</a></li>
   <li><a href="http://mylzh.net/content.php?250-rift_news">Rift: Planes of Telara</a></li>
   <li><a href="http://mylzh.net/content.php?815">Dota 2</a></li>
   <li><a href="http://mylzh.net/content.php?614-starwar_news">Star Wars: The Old Republic</a></li>
   <li><a href="http://mylzh.net/content.php?247-warcraft_news">World of WarCraft: Mists of Pandaria</a></li>
</ul>
</li>
<li>
<a>TEAM</a>
<ul>
   <li><a href="http://mylzh.net/showgroups.php">Staff & Players</a></li>
   <li><a href="http://mylzh.net/application-forms.php?appid=1">Apply to the Team</a></li>
 <li><a href="http://mylzh.net/content.php?179-Achievements">Team Achievements</a></li>
 <li><a href="http://mylzh.net/forumdisplay.php?112-Report-a-Player">Report a Player</a></li>
</ul>
</li>
<li class="middle_pusher"><a href="http://mylzh.net/content.php?195-About-Us">ABOUT</a>
<ul>
   <li><a href="http://mylzh.net/content.php?182-LzH-in-the-Community">In The Community</a></li>
   <li><a href="http://mylzh.net/content.php?181-Sponsors">Sponsors & Partners</a></li>
   <li><a href="http://mylzh.net/sendmessage.php">Contact Us</a></li>
   <li><a href="http://mylzh.net/content.php?189-Donate">Donate</a></li>
</ul>
</li>
<li>
<a href="http://mylzh.net/competitions.php">EVENTS</a>
<ul>
   <li><a href="http://mylzh.net/tournaments.php">Tournaments</a></li>
   <li><a href="http://mylzh.net/ladders.php?showonly=leagues">Leagues</a></li>
   <li><a href="http://mylzh.net/ladders.php?showonly=ladders">Ladder</a></li>
</ul>
</li>
<li>
<a>LZHTV</a>
<ul>
 <li><a href="http://mylzh.net/content.php?196-Streams">Streams</a></li>
 <li><a href="http://mylzh.net/media.php">Video on Demand </a></li>
</ul>
</li>
<li>
<a>LZHCLUB</a>
<ul>
 <li><a href="http://mylzh.net/forumdisplay.php?128-LzH-Club-Room">Club Forums</a></li>
 <li><a href="http://mylzh.net/forumdisplay.php?130-LzH-Club-Download-Video">Club Videos</a></li>
</ul>
</li>
   <li><a href="http://mylzh.net/content.php?187-Store">STORE</a></li>
   <li><a href="http://mylzh.net/forum.php">FORUMS</a></li>
</ul>
</div>

 

CSS:

#nav {
position: relative;
top: 173px;
left:-80px;
margin-left: auto;
margin-right:auto;
z-index: 1;
width:1300px;
}
#jsddm {
margin: 0;
padding: 0; z-index: 10000;
list-style:none;
}

#jsddm li {
float: left;
font: 12px Arial, sans-serif;
padding-right:5px;
text-align:center;
}
#jsddm li.middle_pusher {
padding-right:280px;
}
#jsddm li a {
display: block;
text-decoration: none;
border-right: 0px solid white;
width: auto;
color: #FFF;
padding-right:10px;
text-shadow: 1px 1px 1px #000;
font-size:18px;
}

#jsddm li ul {
margin: 0px;
padding: 0px;
position: absolute;
visibility: hidden;
border-top: 20px solid #008DAB;
border-right: 1px solid #008DAB;
border-bottom: 1px solid #008DAB;
border-left: 1px solid #046FA3;
z-index: 10000;
}

#jsddm li ul li {
float: none;
display: inline;
z-index: 10000;
}

#jsddm li ul li a {
width: auto;
background: #07182A;
padding: 4px;
z-index: 10;
}

#jsddm li ul li a:hover {
background: #046FA3;
z-index: 10;
}

see here

Link doesn't exists

Link doesn't exists

 

Yes it does

Not sure but this could help.

#nav ul li:hover ul
{
visibility:visible;
}

I also suggest to use display instead of visibility to make the submenus invisible.

Yes it does

When I was testing, it didn't work Sorry for that - it's O.K. now.

Yeah, I never use visibility, but this website was handed to me in a job after 2 others had been working on it and they're both very inexperienced. :/ That's for the links, I'll come back if no help.