ul#topnav {
margin: 0; padding: 0;
float: left;
width: 100%;
list-style: none;
position: relative; 
font-size: 11px;
font-family: Tahoma;
background:  url(../../images/arkaSiyah.gif) repeat-x;
}

ul#topnav li {
float: left;
margin: 0; padding: 0;
border-right: 1px solid #646464; 
}
ul#topnav li a {
padding: 10px 15px;
display: block;
color: #f0f0f0;
text-decoration: none;
}
ul#topnav li:hover { background: #1376c9 url(../../images/defter.gif) repeat-x; }

ul#topnav li span {
float: left;
padding: 15px 0 ;
position:absolute;
left: 0px; top: auto;
display: none; 
width: 100%;
background: #1376c9 url(../../images/defter.gif) repeat-x;
color: #fff;

-moz-border-radius-bottomright: 5px;
-khtml-border-radius-bottomright: 5px;
-webkit-border-bottom-right-radius: 5px;

-moz-border-radius-bottomleft: 5px;
-khtml-border-radius-bottomleft: 5px;
-webkit-border-bottom-left-radius: 5px;
}
ul#topnav li:hover span { display: block; } 
ul#topnav li span a { display: inline; }
ul#topnav li span a:hover {text-decoration: underline;}