Bug : souligné se transforme en surligné ?

Merci mimigenie de ta réponse !

Tout d'abord, je dois préciser que je ne suis pas un spécialiste...
Je n'ai pas de feuille de style indépendante, mais voici tout ce qui est entre les balises "style" (il y a beaucoup de choses...). Merci de votre aide :
<style type="text/css" media="all">
a:link {
text-decoration: none;
color: #000099;
}
#ensemble {
width: 900px;
margin-left: auto;
margin-right: auto;
font-family: Arial,Helvetica,sans-serif;
color: #000000;
line-height: 1.1em;
text-align: left;
height: auto;
}
#defilant {
margin: 5px;
line-height: 20px;
}
#menu {
width: 900px;
text-align: left;
}
#nav, #nav ul {
margin: 0 0 1em;
padding: 0;
background: #f4ebcc none repeat scroll 0% 50%;
float: left;
width: 900px;
list-style-type: none;
list-style-image: none;
list-style-position: outside;
line-height: 1.25em;
font-weight: bold;
}
#nav a {
padding: 4px 8px;
display: block;
width: 8em;
color: #483926;
text-decoration: none;
}
#nav a.daddy {
background: transparent url(flechem.gif) no-repeat scroll right center;
}
#nav li {
padding: 0;
float: left;
width: 8em;
}
#nav li ul {
margin: 0;
position: absolute;
left: -999em;
height: auto;
width: 12.8em;
font-weight: normal;
}
#nav li li {
padding-right: 1.5em;
width: 12.7em;
}
#nav li ul a {
width: 12.8em;
}
#nav li ul ul {
margin: -1.9em 0 0 12.8em;
}
#nav li:hover ul ul, #nav li:hover ul ul ul, #nav li.sfhover ul ul, #nav li.sfhover ul ul ul {
left: -999em;
}
#nav li:hover ul, #nav li li:hover ul, #nav li li li:hover ul, #nav li.sfhover ul, #nav li li.sfhover ul, #nav li li li.sfhover ul {
border-right: 1px solid #e6cc80;
border-bottom: 1px solid #e6cc80;
left: auto;
}
#nav li:hover, #nav li.sfhover {
background: #e6cc80 none repeat scroll 0% 50%;
}
#grand_cadre {
clear: left;
}
#grande_gauche {
}
.titre_actus {
color: #2F7CFD;
font-family: Verdana;
font-size: 12pt;
font-weight: bold;
line-height: 25px;
background-color: #C7DCFE;
border-top: aucun #93BBFD;
border-right: 1px solid #93BBFD;
border-bottom: 1px solid #93BBFD;
border-left: none #93BBFD;
}
.Style14 {
font-size: 11px;
}
.Style29 {
color: #990000;
font-weight: bold;
font-size: 11pt;
}
#encart {
border-style: solid;
border-width: 1px;
position: relative;
float: right;
clear: right;
font-family: Tahoma;
font-size: 10px;
color: #cc6600;
}
.titre_tele {
font-family: Verdana;
font-size: 16pt;
color: #005B5B;
line-height: 2em;
font-weight: normal;
font-style: italic;
vertical-align: middle;
border: 4px solid #FF5353;
margin: 10px;
}
a:visited {
text-decoration: none;
color: #000099;
}
a img {
border: none;
}
* {
-moz-box-sizing: border-box;
font-size: 10pt;
vertical-align: top;
}
body {
margin: 0;
background-image: url(fond9.GIF);
background-position: center center;
text-align: center;
}
a:hover {
text-decoration: underline;
color: #cc6600;
}
a:active {
text-decoration: none;
color: #0000cc;
}
.Style39 {
color: #52450c;
font-weight: bold;
line-height: 1.2;
}
.Style41 {
color: #52450c;
}
.StyleNormal {
font-size: 10pt;
font-family: Arial, Helvetica, sans-serif;
padding-left: 10px;
}
.Style43 {
font-family: Georgia, "Times New Roman", Times, serif;
font-weight: bold;
font-size: 14pt;
line-height: 20pt;
}
.sstitre {
font-family: Arial, Helvetica, sans-serif;
font-size: 11pt;
line-height: 15pt;
}
#promo {
border: 1px solid #990000;
padding: 5px;
margin: 0px;
}
#edito {
border: 1px solid #A3A3A3;
padding: 7px;
margin: 0px;
}
#rentree {
padding: 2px;
font-family: Arial, Helvetica, sans-serif;
border-right: 1px solid #666666;
}
.Style50 {
color: #990000;
font-weight: bold;
font-size: 10pt;
line-height: 12pt;
}
.StyleNormal1 {font-size: 11pt;
font-family: Arial,Helvetica,sans-serif;
}
.Style51 {color: #000000}
.Style54 {
font-size: 14px;
line-height: 1.1;
}
.Style55 {
font-size: 15px;
font-weight: bold;
}
.Style64 {font-size: 14px}
.Style65 {color: #990000; font-weight: bold; font-size: 12pt; line-height: 17pt; font-family: Georgia, "Times New Roman", Times, serif; }
.Style66 {font-family: Arial, Helvetica, sans-serif; font-weight: bold; font-size: 14pt; line-height: 20pt; }
.Style68 {color: #FFFFFF}
.Style69 {color: #FFFFFF; font-style: italic; }
</style>

...et bon courage, je comprends que mon code est un peu "brouillon"...

merci ;)
mais il n'y a pas si longtemps on était a ta place ....
si c'est bon, mets le post en résolu, merci

Ca y est, c'est résolu

Nicolas