salve a tutti , rispolverando un vecchio progettino delle superiori mi sono accorto che ho dei problemi con il css se uso come browser mozilla forefox , mentre usando IE tutto fila liscio.
Su mozilla il css risulta proprio non caricato , non si tratta di diversi posizionamenti dei div ma è come se non esistesse il css.

Posto il css quà sotto (non è il massimo ma non capisco perchè su firefox non riesce nemmeno a leggerlo) :

* { padding: 0; margin: 0; }
h2 {
font-family: Arial, Helvetica, sans-serif;
font-size: 24px;
color:#191970;
}
h3 {
font-family: Arial, Helvetica, sans-serif;
font-size: 15px;
color:grey;
}
h4 {
font-family: Arial, Helvetica, sans-serif;
font-size: 19px;
color:black;
}
h5 {
font-family: Arial, Helvetica, sans-serif;
font-size: 12px;
color:black;
}

#Titolo{
background-image:url('C:/test/tesina/img/prossima_uscita2.jpg');
background-repeat: no-repeat;
background-position: center;
background-color:black;
border: 5px solid #DCDCDC;
font-family: Comic Sans ms, Helvetica, sans-serif;
color:#ffffff;
margin-left:2%;
margin-right:2%;
text-align:center;
margin-bottom:0px;
margin-top:40px;
font-size: 30px;
height:230px;
padding-top:32px;
padding-bottom:32px;
}


table, td, th {
border:2px solid #DCDCDC;
padding:10px;
margin-top:50px;
margin-left: auto;
margin-right: auto;
color:black;
background-color:white;
text-align:center;
}

th {
background-color:#FFFFCC;
color:black;
}


#sinistra{

width: 25%;
float:left;
padding-left:30px;
padding-right:100px;
text-align:center;

}

#sinistracarrello{
width: 40%;
float:left;
padding-left:30px;
padding-right:100px;
text-align:right;

}
#centrodestracarrello{
width:35%;
float:left;
text-align:left;
padding-left:20px;
padding-right:40px;
}
#registrazione{
width: 60%;
float:left;
padding-left:30px;
padding-right:30px;
text-align:right;
min-height:378px;

}
#registrazione2{
width: 30%;
float:right;
padding-left:30px;
padding-right:30px;
text-align:right;
min-height:378px;
}
#centro{
width: 55%;
float:left;
text-align:left;
padding-left:20px;
padding-right:20px;
}
#centrodestra{
width:47%;
float:left;
text-align:left;
padding-left:60px;
padding-right:40px;
}

#pr-uscite-des{
width:47%;
float:right;
text-align:left;
padding-left:20px;
padding-right:20px;
min-height:750px;

}
#pr-uscite-sin{
width: 45%;
float:left;
text-align:center;
padding-left:20px;
padding-right:20px;
min-height:750px;

}
#pr-uscite-des2{
width:47%;
float:right;
text-align:left;
padding-left:20px;
padding-top:160px;
padding-right:20px;
min-height:400px;

}
#pr-uscite-sin2{
width: 45%;
float:left;
text-align:center;
padding-left:20px;
padding-top:100px;
padding-right:20px;
min-height:400px;

}

#destra{
width: 20%;
float:right;
text-align:right;
padding-left:40px;
padding-right:40px;
}

#content
{

background-color:#ffffff;
/*background-image:url('C:/test/tesina/img/samcinema2.jpg');
background-repeat: no-repeat;
background-position: right bottom; */
width: auto;
color: grey;
border: 0px solid #E4E4E4 ;
margin-left:2%;
margin-right:2%;
padding: 10px;
min-height:500px;
text-align:center;
padding-top:40px;
padding-bottom:5px;
padding-left:30px;
padding-right:30px;
}
#contentscheda
{

background-color:#ffffff; /*
background-image:url('C:/test/tesina/img/samcinema2.jpg');
background-repeat: no-repeat;
background-position: right bottom;*/
width: auto;
color: grey;
border: 0px solid #E4E4E4 ;
margin-left:2%;
margin-right:2%;
min-height:500px;
padding-top:40px;
padding-bottom:5px;
padding-left:0px;
padding-right:0px;
}

#scritta_scorrevole{
width: auto;
background-color:#F0F8FF;
background-repeat: repeat;
margin-left: 2%;
margin-right:2%;
padding: 10px;
padding-left:250px;
padding-right:250px;
border: 5px solid #E4E4E4;
color:black;
font-family: Comic Sans ms, Helvetica, sans-serif;
font-weight: bold;
font-size: 25px;
}
#logo{
background-color:#ffffff;
background-image:url('C:/test/tesina/img/samcinema2.jpg');
background-repeat: no-repeat;
background-position: right bottom;
min-height:160px;
margin-left:2%;
margin-right:2%;

}

#footer
{
width: auto;
color: #333;
border: 5px solid #E4E4E4;
background-color:#F0F8FF;
margin-left: 2%;
margin-right:2%;
margin-bottom:2%;
padding: 10px;
}
#content a
{ text-align:center;
font-family: Arial, Helvetica, sans-serif;
font-size: 12px;
color:blue;
}

#ricerca
{
margin-left:2%;
margin-right:2%;
text-align:right;
font-family:lucida console,Arial,serif;
font-size:12px;
background-color: #E4E4E4 ;
padding:10px;
color: #191970;
}

#ricerca h1
{
font-family:lucida console,Arial,serif;
font-size:12px;
}

body {
background-color:#000000 ;
margin-top: 40px;
font-family: Arial, Helvetica, sans-serif;
font-size: 13px;
}

#menu{
padding:0;
font-family:lucida console,Arial,serif;
font-size:20px;
display:inline
margin: 0px 0px 0px 20px;
height: auto;
background-color: #F0F8FF ;
float: middle;
width: auto;
height: 60px;
margin-left:2%;
margin-right:2%;
border: 5px solid #DCDCDC;

}


#menu ul{
margin: 0px 0px px 0px;
padding: 0px;
vertical-align:middle;
list-style: none;
line-height:normal ;
}

#menu li{
position: relative;
float: left;
list-style: none;
margin: 0;
padding:0;
border-bottom: 2px solid #ddd;
border-left: 2px solid #ddd;
display: block;

}

#menu ul li{
font-family:verdana,Arial,sans serif;
font-size:1em;
width:200px;
}

#menu ul ul li{
font-family:verdana,Arial,sans serif;
font-size:0.7em;
}


#menu li a{
width:200px;
height: 60px;
display: block;
text-decoration:none;
text-align: center;
line-height: 30px;
color: #333;
background: #F0F8FF;


}

#menu li a:hover{
background: #ffffff;
}

#menu ul ul{
position: absolute;
top: 60px;
visibility: hidden;


}

#menu ul li:hover ul {
visibility:visible;

}

#menu ul ul ul li {
visibility: hidden;
left:150px;
top:-30px;
}

#menu ul ul li:hover ul li {
visibility:visible;
}