update css.php

Fixed the sytnax issue

themes/default/css.php

@@ -350,11 +350,11 @@ else {
 	elseif (!empty($_SESSION['theme']['login_background_color']) && !empty($_SESSION['theme']['login_background_color'][0])) {
 		$background_colors[0] = $_SESSION['theme']['login_background_color'][0];
 	}
-	elseif ($_SESSION['theme']['background_color_enabled']) && $_SESSION['theme']['background_color_enabled'] == 'true' && !empty($_SESSION['theme']['background_color'][0]) && !empty($_SESSION['theme']['background_color'][1])) {
+	elseif ($_SESSION['theme']['background_color_enabled'] && $_SESSION['theme']['background_color_enabled'] == 'true' && !empty($_SESSION['theme']['background_color'][0]) && !empty($_SESSION['theme']['background_color'][1])) {
 		$background_colors[0] = $_SESSION['theme']['background_color'][0];
 		$background_colors[1] = $_SESSION['theme']['background_color'][1];
 	}
-	elseif $_SESSION['theme']['background_color_enabled']) && $_SESSION['theme']['background_color_enabled'] == 'true' && !empty($_SESSION['theme']['background_color'][0])) {
+	elseif ($_SESSION['theme']['background_color_enabled'] && $_SESSION['theme']['background_color_enabled'] == 'true' && !empty($_SESSION['theme']['background_color'][0])) {
 		$background_colors[0] = $_SESSION['theme']['background_color'][0];
 	}
 }