.menutop {
width:750px;
height: 20px;
background-color: #111288;
margin:0 auto;
}


.menutop a:link img { border: none }
.menutop a:visited img { border: none }
.menutop a:active img { border: none }


.menutop a:hover img {
filter:alpha(opacity=50);   
-moz-opacity: 0.50;   
opacity: 0.50;
}