photomakes,<script language=\"javascript\" type=\"text/javascript\">date = new Date();a = date.getHours();if (a > 17 || a < 10 ) {document.write(\"<link rel=\'stylesheet\' href=\'{THEME}/css/header_day.css\' type=\'text/css\'>\");}elseif (a > 9 || a < 18) {document.write(\"<link rel=\'stylesheet\' href=\'{THEME}/css/style.css\' type=\'text/css\'>\");}</script>Где header_day.css — стили для дня.