aggiustare l'evidenziazione della lingua selezionata sul tema fervens

on the original theme is all right:
http://thatchamhistoricalsociety.org.uk/?theme=fervens
instead on my website , it has stopedto go the highlighing in white color of selected languages
www.rnhotels.com
here you can find the download for this theme:
http://ftp.drupal.org/files/projects/fervens-6.x-1.0-beta1.tar.gz
I hope that someone can help me.