.preload1 {background: url('Hover-Arrow.gif');}
.preload2 {background: url('Hover-Arrow.gif');}

/* I think this set defines the main menu bar. Margin is aound entire bar. */
     #nav {padding:0; margin:0; height:35px; url('three_0.gif') repeat-x; position:relative; z-index:500;
     font-family:arial, verdana, sans-serif; list-style-type:none}

#nav li.top {display:block; float:left; height:40px;}

/* Button font? */
     #nav li a.top_link {display:block; float:left; height:35px; line-height:33px; color:#ccc; text-decoration:none;
     font-size:12px; font-weight:bold; cursor:pointer;background: url('three_0.gif');; text-align:center}

/* This sets dimension of single level buttons */
     #nav li a.top_link span {float:left; display:block; height:35px; background: url('Button-NoArrow.gif') no-repeat right top;;
     width:155px}

/* This sets dimensions of buttons with menus below them. */
     #nav li a.top_link span.down {float:left; display:block; height:35px; background: url('Button-Arrow.gif') no-repeat right top;;
     width:155px}

/* I think this selects button pictures to display upon mouse hover, but why 3? */
     #nav li:hover a.top_link {color:#FFFFFF; background: url('Hover-Arrow.gif') no-repeat;}
     #nav li:hover a.top_link span {background:url('Hover-NoArrow.gif') no-repeat right top;}
     #nav li:hover a.top_link span.down {background:url('Hover-Arrow.gif') no-repeat right top;}

/* Default list styling. Higher z-index elements will lie on top of lower z-index elements. */
     #nav li:hover {position:relative; z-index:200;}

/* Establishes solid color rectangle below buttons */
     #nav li:hover ul.sub  {left:1px; top:35px; background: #0105B5; padding:10px; border:2px solid #0105B5;
     white-space:nowrap; width:130px; height:auto; z-index:300;}

/* Established highlight box in drop down menu */
     #nav li:hover ul.sub li a {display:block; font-size:12px; height:18px; width:130px; line-height:18px; 
         text-align:center; color:#CCCCCC; text-decoration:none; border:2px solid #0105B5;}
     #nav li ul.sub li a.fly {background:#000000 url('arrow.gif') no-repeat 80px 6px;}


/* This is the rectangle around drop down menu text. */
     #nav li:hover ul.sub li a:hover {background:#0105B5; color:#FFFFFF; border-color:#FFFFFF;}
     #nav li:hover ul.sub li a.fly:hover

/* I think the rest of these entries are the sub-menu extensions to the side of the pull-down. */

#nav li:hover li:hover ul,
#nav li:hover li:hover li:hover ul,
#nav li:hover li:hover li:hover li:hover ul,
#nav li:hover li:hover li:hover li:hover li:hover ul
{left:90px; top:-4px; background: #383F5f; padding:3px; border:1px solid #383F5f; white-space:nowrap; width:90px; z-index:400; height:auto;}

#nav ul, 
#nav li:hover ul ul,
#nav li:hover li:hover ul ul,
#nav li:hover li:hover li:hover ul ul,
#nav li:hover li:hover li:hover li:hover ul ul
{position:absolute; left:-9999px; top:-9999px; width:0; height:0; margin:0; padding:0; list-style:none;}