I have a CSS drop down that works fine when left aligned in both Firefox and IE, but when I try to center the entire menu so that it aligns with my site, the sublevel dropdowns dropdown down to the side of the main rollover and not directly below it. Also, the 1st item of the sublevel is hidden behind the main nav on the right of the button rollover. I've been trying to figure this out for a few weeks now and have had no luck.

Here is my code:

CSS for IE:
Code:
div.menu {
	margin: 0 auto;
	text-align:center;
}

div.menu
{
position:relative;
height:30px;
width:840px;
display:block;
margin: 0 auto;
text-align:center;
}

ul.menu
{
top:0px;
left:0px;
position:relative;
padding:0px;
display:block;
float:left;
}

ul.menu li {
float:left;
display:block;
}

ul.menu ul
{
position:relative;
margin: 0 auto;
width:840px;
top:0px;
left:0px;
padding:0px;
display:block;
}

ul.menu ul li
{
display:block;
float:right;
position:relative;
top:0px;
left:0px;
}

a.menu
{
display:block;
width:100px;
height:30px;
margin-top:-4px;
}
a.menu:hover
{
display:block;
}
CSS for Non-IE browsers:
Code:
div.menu
{
width:100%;
position:relative;
height:30px;
}

ul.menu
{
position:relative;
padding:0px;
margin:0px;
list-style-type:none;
float:left;
}

ul.menu ul
{
position:absolute;
list-style-type:none;
padding:0px;
margin:0px;
display:none;
margin-left:0px;
z-index:1;
}


ul.menu:hover ul
{
display:block;
}

a.menu
{
display:block;
width:100px;
text-decoration:none;
border-bottom: solid 1px black;
margin-bottom:0px;
}
a.menu:hover
{
display:block;
}
HTML:
Code:
<body onload="MM_preloadImages('../Pictures/CoachesY.png','../Pictures/ScheduleY.png','../Pictures/RostersY.png','../Pictures/Sub Buttons/CoachHenriottY.jpg','../Pictures/Sub Buttons/CoachWitteY.jpg','../Pictures/Sub Buttons/CoachSchneiderY.jpg','../Pictures/Sub Buttons/CoachReevesY.jpg','../Pictures/Sub Buttons/FreshmanY.jpg','../Pictures/Sub Buttons/JVY.jpg','../Pictures/Sub Buttons/VarsityY.jpg','../Pictures/CampsY.png','../Pictures/SummerInfoY.png','../Pictures/LinksY.png','../Pictures/YouthInfoY.png','../Pictures/DirectionsY.png')" align="center">
<table width="690" align="center" bgcolor=#8560A9>
  <tr><td bordercolor="#FFFFFF" bgcolor="#8560A9">
<table width="690" border="0" align="center">
  <tr bgcolor="#FFFFFF" height="227">
    <td height="15" bgcolor="#8560A9"><div id="center"><img src="../Pictures/TitlePhoto.jpg" alt="Lady Elks Basketball" width="800" height="200" /><br />
	  <div class="menu">
   <ul class="menu">
      <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image1','','../Pictures/CoachesY.png',1)"><img src="../Pictures/CoachesP.png" name="Image1" width="100" height="30" border="0" id="Image1" /></a>
         <ul>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image4','','../Pictures/Sub Buttons/CoachHenriottY.jpg',1)"><img src="../Pictures/Sub Buttons/CoachHenriottP.jpg" name="Image4" width="100" height="30" border="0" id="Image4" /></a></li>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image5','','../Pictures/Sub Buttons/CoachWitteY.jpg',1)"><img src="../Pictures/Sub Buttons/CoachWitteP.jpg" name="Image5" width="100" height="30" border="0" id="Image5" /></a></li>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image6','','../Pictures/Sub Buttons/CoachSchneiderY.jpg',1)"><img src="../Pictures/Sub Buttons/CoachSchneiderP.jpg" name="Image6" width="100" height="30" border="0" id="Image6" /></a></li>
			<li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image7','','../Pictures/Sub Buttons/CoachReevesY.jpg',1)"><img src="../Pictures/Sub Buttons/CoachReevesP.jpg" name="Image7" width="100" height="30" border="0" id="Image7" /></a></li>
         </ul>
      </li>
   </ul>
   <ul class="menu">
      <li><a class="menu" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image2','','../Pictures/ScheduleY.png',1)"><img src="../Pictures/ScheduleP.png" name="Image2" width="100" height="30" border="0" id="Image2" /></a>
         <ul>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image8','','../Pictures/Sub Buttons/FreshmanY.jpg',1)"><img src="../Pictures/Sub Buttons/FreshmanP.jpg" name="Image8" width="100" height="30" border="0" id="Image8" /></a></li>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image9','','../Pictures/Sub Buttons/JVY.jpg',1)"><img src="../Pictures/Sub Buttons/JVP.jpg" name="Image9" width="100" height="30" border="0" id="Image9" /></a></li>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image10','','../Pictures/Sub Buttons/VarsityY.jpg',1)"><img src="../Pictures/Sub Buttons/VarsityP.jpg" name="Image10" width="100" height="30" border="0" id="Image10" /></a></li>
         </ul>
     </li>
   </ul>
   <ul class="menu">
      <li> <a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image3','','../Pictures/RostersY.png',1)"><img src="../Pictures/RostersP.png" name="Image3" width="100" height="30" border="0" id="Image3" /></a>
         <ul>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image13','','../Pictures/Sub Buttons/FreshmanY.jpg',1)"><img src="../Pictures/Sub Buttons/FreshmanP.jpg" name="Image13" width="100" height="30" border="0" id="Image13" /></a></li>
            <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image12','','../Pictures/Sub Buttons/JVY.jpg',1)"><img src="../Pictures/Sub Buttons/JVP.jpg" name="Image12" width="100" height="30" border="0" id="Image12" /></a></li>
			<li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image11','','../Pictures/Sub Buttons/VarsityY.jpg',1)"><img src="../Pictures/Sub Buttons/VarsityP.jpg" name="Image11" width="100" height="30" border="0" id="Image11" /></a></li>
         </ul>
      </li>
   </ul>
   <ul class="menu">
   	  <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image14','','../Pictures/CampsY.png',1)"><img src="../Pictures/CampsP.png" name="Image14" width="100" height="30" border="0" id="Image14" /></a></li>
   </ul>
   <ul class="menu">
   <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image15','','../Pictures/SummerInfoY.png',1)"><img src="../Pictures/SummerInfoP.png" name="Image15" width="100" height="30" border="0" id="Image15" /></a></li>
   </ul>
   <ul class="menu">
   <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image16','','../Pictures/LinksY.png',1)"><img src="../Pictures/LinksP.png" name="Image16" width="100" height="30" border="0" id="Image16" /></a></li>
   </ul>
   <ul class="menu">
   <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image17','','../Pictures/YouthInfoY.png',1)"><img src="../Pictures/YouthInfoP.png" name="Image17" width="100" height="30" border="0" id="Image17" /></a></li>
   </ul>
   <ul class="menu">
   <li><a class="menu" href="#" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image18','','../Pictures/DirectionsY.png',1)"><img src="../Pictures/DirectionsP.png" name="Image18" width="100" height="30" border="0" id="Image18" /></a></li>
   </ul>
</div><br />
    </div>
Any help would be greatly appreciated. Thank you.