.Menu {float:left; display:inline; margin:99px 0 0 280px; padding:0; list-style:none; height:31px; position:relative; z-index:500; }
.Menu li.top { margin:1px 0 0 0;  display:block; float:left;}

.Menu li a.top_link {display:block; float:left; color:#4d7ab0; width:195px; text-decoration:none; padding:0; text-align:center; font:normal 22px Georgia, serif; color:#666; cursor:pointer; background:url(../images/bt-onglets-menu.png) no-repeat; }
.Menu li a.top_link span {float:left; display:block; height:31px; width:195px; padding:10px 0 0 0 /* Positionner le texte du menu */ }
.Menu li a.top_link span.down {float:left; display:block; }

.Menu li a.top_link:hover { color:white; background:url(../images/bt-onglets-menu.png) 0 -41px no-repeat; }
.Menu li a.top_link:hover span { color:white; background:url(../images/bt-onglets-menu.png) 0 -41px no-repeat; } /* Fond du Texte HOVER */
.Menu li a.top_link:hover span.down { color:white; background:url(../images/bt-onglets-menu.png) 0 -41px no-repeat; } /* Fond du Texte HOVER + Menu SUB */

.Menu li:hover > a.top_link { color:white; background:url(../images/bt-onglets-menu.png) 0 -41px no-repeat; }
.Menu li:hover > a.top_link span {}
.Menu li:hover > a.top_link span.down {}

/* Style the list OR link hover. Depends on which browser is used */
.Menu a:hover {visibility:visible; position:relative; z-index:200;}
.Menu li:hover {position:relative; z-index:200;}

/* keep the 'next' level invisible by placing it off screen. */
.Menu ul, 
.Menu :hover ul {position:absolute; left:-9999px; top:-9999px; width:0; height:0; margin:0; padding:0; list-style:none;}

.Menu :hover ul.sub {left:0; top:41px; background: black; filter:alpha(opacity=80); opacity: 0.80; padding:5px; border:1px solid #666; white-space:nowrap; width:auto; height:auto; z-index:300;}
.Menu :hover ul.sub li {display:block; height:30px; position:relative; width:auto; font-weight:normal; text-align:left; }
.Menu :hover ul.sub li a {display:block; font:normal 20px arial, sans-serif; height:30px; line-height:30px; text-indent:5px; padding-right:5px; color:white; text-decoration:none;}
.Menu :hover ul.sub li a:hover {background:#4d7ab0; color:white;}