@-moz-document url-prefix(http://www.reichelt.de/) {  
#m_content {width: 300px !important;}
#r_content {left: 300px !important;}
.menu_stef,.menu_stef0,.menu_stef1 {width:280px !important;}
.menu_stef0 .content_0 {width:280px !important;}
}