Come vuoi, comunque i infilo il codice, che, se vuoi, puoi piazzare anche direttamente sul tema, invece di andare a cercare ogni div o classe
@-moz-document url-prefix('http://bubs.altervista.org/index.php') {body, td, th, tr { color: #CCC !important; }
body, td, th, tr { color: #CCC !important; }
.dropmenu a, a:link, a:visited { color: white !important; }
body { background: -webkit-linear-gradient(#333, #151515) !important;background: -moz-linear-gradient(#333, #151515) !important;background: linear-gradient(#333, #151515) !important; }
#header { background: -webkit-linear-gradient(#252525, #111) !important;background: -moz-linear-gradient(#252525, #111) !important;background: linear-gradient(#252525, #111) !important; border-radius: 15px 15px 0 0 !important; }
#upper_section { background: -webkit-linear-gradient(#444, transparent) !important;background: -moz-linear-gradient(#444, transparent) !important; background: linear-gradient(#444, transparent) !important;border-radius: 15px !important; padding: 15px 10px !important; }
#content_section, #footer_section { background: #111 !important; }
h3.titlebg a, h3.titlebg, h4.titlebg, h4.titlebg a { color: #CCC !important; }
.windowbg2 { background: #333 !important; color: inherit !important;}
.windowbg, #preview_body {background: #292929 !important; color: inherit !important; }
div.cat_bar { background: -webkit-linear-gradient(#222, black) !important;background: -moz-linear-gradient(#222, black) !important;background: linear-gradient(#222, black) !important; border-radius: 5px !important; }
.navigate_section ul { border-top: 1px solid #444 !important; }
.roundframe { border-radius: 5px !important; border: 2px solid #555 !important; padding-top: 10px !important; padding-bottom: 5px !important; }
div.title_barIC { background: -webkit-linear-gradient(#444, #222) !important;background: -moz-linear-gradient(#444, #222) !important;background: linear-gradient(#444, #222) !important; }
#footer_section { background: -webkit-linear-gradient(#111, black) !important; background: -moz-linear-gradient(#111, black) !important;background: linear-gradient(#111, black) !important; border-radius: 0 0 15px 15px !important; }
.catbg, .catbg2, tr.catbg td, tr.catbg2 td, tr.catbg th, tr.catbg2 th, .titlebg, .titlebg2 td, div.frame, span.upperframe, span.upperframe span, span.lowerframe, span.lowerframe span, .roundframe, span.botslice, span.botslice span,span.topslice, span.topslice span, .buttonlist ul li a span, .buttonlist ul li a.active span, .dropmenu li a span, .dropmenu li a span, .dropmenu li a { background: none !important; }
.description, .description_board, .plainbox { background: #222 !important; }
table.table_grid td { border-bottom: 1px solid #111 !important;
border-right: 1px solid #111 !important; }
.stickybg, .stickybg2 { background: #444 !important; }
textarea, input, button, select { background: black !important; color: white !important; border: 1px solid #555 !important; padding: 2px; }
blockquote.bbc_standard_quote { background-color: #222 !important; color: #CCC !important; border: 2px solid #555 !important; border-radius: 5px !important; }
.buttonlist ul li a { background: #333 !important; border-radius: 5px !important; }
.buttonlist ul li a:hover { background: -webkit-linear-gradient(95deg, #111, #222, #111) !important; background: -moz-linear-gradient(95deg, #111, #222, #111) !important;background: linear-gradient(95deg, #111, #222, #111) !important;color: #555 !important; border-radius: 5px; }
.buttonlist ul li a.active:hover { background: -webkit-linear-gradient(95deg, black, #111, black) !important;background: -moz-linear-gradient(95deg, black, #111, black) !important;background: linear-gradient(95deg, black, #111, black) !important; color: #555 !important; border-radius: 5px; }
code.bbc_code{ background: #222 !important; color: #CCC !important; }
h1, h2, h3, h4, h5, h6 { color: inherit !important; }
.dropmenu li a.firstlevel { background: #333 !important; border-radius: 2px !important; padding: 0 0 0 5px !important;}
.dropmenu li a.firstlevel:hover { background: #555 !important; }
.dropmenu li ul { background: #333 !important; border-top: 1px solid #999 !important; padding: 0px !important}
.dropmenu li ul li:hover { background: #222 !important;}
.geshi { background: #DDD !important; color: #333 !important;}
.geshi ol { list-style-type: none !important; padding: 0 !important; margin: 0 !important; }
.geshi li { background: #DDD !important; border-bottom: none !important; border-left: none !important;}
::selection { background-color: #555 !important; }
.geshi ol li div::selection, .geshi ol li span::selection { background-color: #BBB !important; }
#footer_section div.frame { padding: 10px 0 0 0 !important; }
.topic_table td.lockedbg2, .topic_table td.lockedbg { background: #111 !important;}
.navbar-default {background-color: #444;}
.body_content {background: grey;}
.body_content span.arrow-left {border-color: transparent #818181 rgba(20, 20, 20, 0) transparent;}
}