delete "leave a message" comment box

Hello I am using catch box and have a problem with making the "leave a message" comment box under each page (it says "leave a message" in German) invisible or deleting it. I do not only want to deactivate them but make them completely invisible. Is this possible and if so how? I would need a step by step instruction as I am not really fit with CSS. Can anyone please help me? Many thanks in advance. Regards, MM