Problemas Explorer y firefox

[luchozero]

os dejo el CSS:

*/
body {
margin:0;
padding:0;
background:url(img/bk_menu.jpg) repeat-x;
}
ol{
list-style:none;
}
* {
margin:0;
padding:0;
}
img {
padding:0;
margin:0;
}
#header {
width:739px;
height:90px;
margin:auto;
padding:80px 120px 80px 120px;
text-align:center;
background:url(img/header.jpg) no-repeat;
font-size:70px;
}
#header a {
text-decoration:none;
}
#nav {
margin:auto;
width:979px;
height:40px;
padding:0;
}
#nav ul {
padding:0;
margin:0;
list-style:none;
display:block;
}
#nav ul li {
margin:0;
float:left;
list-style:none;
display:block;
font-weight:bold;
font-family:Arial;
font-size:15px;
padding:12px 10px 0 10px;
}
#nav ul li a{
text-decoration:none;
color:#000000;
}
#nav ul li a:hover{
text-decoration:underline;
color:#000000;
}
#content {
width:979px;
margin:auto;
background:url(img/bk_wraper.jpg) repeat-y;
}
#sidebar_izquierdo {
float:left;
width:224px;
margin-left:10px;
margin-top:15px;
}
#main {
width:511px;
float:left;
}
#sidebar {
margin-top:15px;
width:224px;
float:left;
}
.clear {
float:none;
clear:both;
}
#footer {
width:979px;
margin:auto;
background:url(img/bk_cierra_wraper.jpg) no-repeat top;
text-align:center;
}
#pedo {
height:22px;
text-align:center;
background: url(img/bk_pedo.jpg) repeat-x;
}
#pedo a{
font-family:Arial;
font-size:12px;
font-weight:bold;
text-decoration:none;
color:#000000;
}
#pedo a:hover{
text-decoration:underline;
}
.atencion{
color:#ff33ff;
font-family:Arial;
font-size:15px;
font-weight:bold;
margin-top:10px;
}
.cont {
font-family:Arial;
font-size:13px;
color:#000000;
}
.finales {
margin:10px 0 10px 0;
color:#0000ff;
font-family:Arial;
font-size:14px;
font-weight:bold;
}
.finales a{
color:#0000ff;
text-decoration:none;
font-family:Arial;
font-size:14px;
font-weight:bold;
}
.finales a:hover{
text-decoration:underline;
}
.post_title {
padding:8px 0 0 15px;
margin-top:15px;
height:29px;
background:url(img/bk_title.jpg) no-repeat;
color:#FFFFFF;
font-family:Arial;
font-size:16px;
font-weight:bold;
}
.post_title a{
text-decoration:none;
color:#FFFFFF;
}
..post_title a:hover{
text-decoration:underline;
}
#main img {
float:left;
padding-right:3px;
}
#main p {
padding:15px;
font-family:Arial;
color:#000000;
font-size:14px;
}
.bloque {
height:35px;
background:url(img/bk_bloque.jpg) no-repeat;
padding:10px 20px 0 20px;
}
.bloque h1 {
font-family:Arial;
font-size:15px;
font-weight:bold;
color:#0000FF;

}
.fin_bloque {
height:14px;
background:url(img/bk_bloque_fin.jpg) no-repeat;
margin-bottom:20px;
}
..cont_bloque {
background:url(img/bk_bloque_2.jpg) repeat-y;
padding:0 20px 0 20px;
}
.cont_bloque p{
text-align:center;
font-family:Arial;
font-size:12px;
color:#000000;
}
.more-link {
display:block;
padding-left:430px;
padding-top:5px;
height:23px;
font-family:Arial;
font-size:14px;
color:#FFFFFF;
font-weight:bold;
background:url(img/bk_mas.jpg) no-repeat;
text-decoration:none;
}
.cont_widget {
background:url(img/categorias.jpg) no-repeat top;
margin:0 0 20px 0;
}
..cont_widget .title{
font-family:Arial;
color:#FFFFFF;
font-size:15px;
font-weight:bold;
padding:9px 0 0 20px;
margin-bottom:10px;
}
.cont_widget ul .cat-item, .cont_widget ul .page_item{
list-style:none;
display:block;
padding:2px 0 2px 20px;
font-family:Arial;
font-size:14px;
color:#000000;
font-weight:bold;
}
.cont_widget ul .cat-item a, .cont_widget ul .page_item a{
text-decoration:none;
color:#000000;
}
.cont_widget ul .cat-item a:hover, .cont_widget ul .page_item a:hover{
text-decoration:underline;
color:#000000;
}



.cont_comun {
background:url(img/categorias.jpg) no-repeat top;
margin:0 0 20px 0;
}
.cont_comun .title{
font-family:Arial;
color:#FFFFFF;
font-size:15px;
font-weight:bold;
padding:9px 0 0 20px;
margin-bottom:10px;
}
.cont_comun ul li, .cont_comun li{
list-style:none;
display:block;
padding:3px 0 3px 20px;
font-family:Arial;
font-size:14px;
color:#000000;
font-weight:bold;
}
.cont_comun ul li a, .cont_comun li a{
text-decoration:none;
color:#000000;
}
.cont_comun ul li a:hover, .cont_comun li a:hover{
text-decoration:underline;
}






/*paginador pagebar ===========================================*/
.pagebar {
-x-system-font:none;
font-family:Arial,Helvetica,sans-serif;
font-size:11px;
font-size-adjust:none;
font-stretch:normal;
font-style:normal;
font-variant:normal;
font-weight:normal;
line-height:normal;
margin:0;
text-align:center;
padding-bottom:10px;
padding-top:20px;
}
.pagebar a, .pageList .this-page {
background:#FFFFFF none repeat scroll 0 0;
border:1px solid #DDDDDD;
padding:2px 6px;
text-decoration:none;
}
.pagebar a:visited {
background:#FFFFFF none repeat scroll 0 0;
border:1px solid #DDDDDD;
padding:2px 6px;
text-decoration:none;
}
.pagebar .break {
background:#FFFFFF none repeat scroll 0 0;
border:medium none;
padding:2px 6px;
text-decoration:none;
}
.pagebar .this-page {
background:#FFFFFF none repeat scroll 0 0;
border-color:#999999;
font-size:13px;
font-weight:bold;
padding:2px 6px;
vertical-align:top;
}
.pagebar a:hover {
background:#336699 none repeat scroll 0 0;
border-color:#009900;
color:#FFFFFF;
text-decoration:none;
}
.pagebar .inactive {
border-color:#999999;
font-size:13px;
font-weight:bold;
padding:2px 6px;
vertical-align:top;
}
h2{
font-size:14px;
font-family:Arial;
}



.datospost {
font-family:Arial;
font-size:12px;
background-color:#C5EEFF;
margin:25px;
padding:5px;
}

img.centered (
pantalla: bloque;
margen izquierda: auto;
margen derecha: auto;
)

img.alignright (
padding: 4px;
margin: 0 0 2px 7px;
pantalla: "inline";
)

img.alignleft (
padding: 4px;
margin: 0 7px 2px 0;
pantalla: "inline";
)

. alignright (
float: right;
)

. alignleft (
flotador: izquierda;
)