<ul id="cssmenu">
         <li><a href="#">Горизонтальное</a>
                 <ul>
                         <li><a href="#">Ссылка 1</a></li>
                         <li><a href="#">Ссылка 2</a></li>
                 </ul>
         </li>
         <li><a href="#">CSS</a>
                 <ul>
                         <li><a href="#">Ссылка 1</a></li>
                         <li><a href="#">Ссылка 2</a></li>
                         <li><a href="#">Ссылка 3</a></li>
                         <li><a href="#">Ссылка 4</a></li>
                         <li><a href="#">Ссылка 5</a></li>
                 </ul>
         </li>
         <li><a href="#">Меню</a>
                 <ul>
                         <li><a href="#">Ссылка 1</a></li>
                         <li><a href="#">Ссылка 2</a></li>
                 </ul>
         </li>
</ul>

/* CSS Document */
ul#cssmenu {
         width:350px;
         margin: 0;
         border: 0 none;
         padding: 0;
         list-style: none;
         background: #003366;
         height: 30px;
         font: bold 12px/28px Verdana, Arial;
         border-left:#003366 1px solid;
}

ul#cssmenu li {
         margin: 0;
         border: 0 none;
         padding: 0;
         float: left;
         display: inline;
         list-style: none;
         position: relative;
         height: 30px;
}

ul#cssmenu ul {
         margin: 0;
         border: 0 none;
         padding: 0;
         width: 160px;
         list-style: none;
         display: none;
         position: absolute;
         top: 30px;
         left: 0;
}

ul#cssmenu ul:after {
         clear: both;
         display: block;
         font: 1px/0px serif;
         content: ".";
         height: 0;
         visibility: hidden;
}

ul#cssmenu ul li {
         width: 150px;
         float: left;
         display: block !important;
         display: inline;
}

/* Main Menu */
ul#cssmenu a {
         border: 0px;
         padding: 0 10px;
         float: none !important;
         float: left;
         display: block;
         background: #003366;
         color: #FFFFFF;
         font: bold 12px/28px Verdana, Arial;
         text-decoration: none;
         height: auto !important;
         height: 1%;
}

/* Main Menu Hover */
ul#cssmenu a:hover,
ul#cssmenu li:hover a,
ul#cssmenu li.iehover a {
         background: #FFFFFF;
         color:#003366;
         border-top:#003366 1px solid;
}

/* Second Menu */
ul#cssmenu li:hover li a,
ul#cssmenu li.iehover li a {
         border-top: 2px solid #FFFFFF;
         float: none;
         background: #003366;
         color: #FFFFFF;
}

/* Second Menu Hover */
ul#cssmenu li:hover li a:hover,
ul#cssmenu li:hover li:hover a,
ul#cssmenu li.iehover li a:hover,
ul#cssmenu li.iehover li.iehover a {
         border-top: 2px solid #FFFFFF;
         background: #FFFFFF;
         color:#003366;
         border:#003366 1px solid;
}

ul#cssmenu ul ul {
         display: none;
         position: absolute;
         top: 0;
         left: 170px;
}

ul#cssmenu li:hover ul ul,
ul#cssmenu li.iehover ul ul {
         display: none;
}

ul#cssmenu li:hover ul,
ul#cssmenu ul li:hover ul,
ul#cssmenu li.iehover ul,
ul#cssmenu ul li.iehover ul {
         display: block;
}

// JavaScript Document
function cssmenuhover()
{
         if(!document.getElementById("cssmenu"))
                 return;
         var lis = document.getElementById("cssmenu").getElementsByTagName("LI");
         for (var i=0;i<lis.length;i++)
         {
                 lis[i].onmouseover=function(){this.className+=" iehover";}
                 lis[i].onmouseout=function() {this.className=this.className.replace(new RegExp(" iehover\\b"), "");}
         }
}
if (window.attachEvent)
         window.attachEvent("onload", cssmenuhover);