Menu Colour

Hi I have asked this question recently but two participants gave me opposite replies, so I am a bit confused. I see from the forums that Tikaram has previously answered my question with a very short piece of CSS code, when this question was asked. I want to update the red colour which appears on the Main Menu which I cannot seem to customise Site URL http://caclearning.site/ The home in the menu appears as red when you access the site and the other navigation e.g biography appear as red when you hover over them. I want them to be another colour. The white standard (no hover is fine) and then to change to a colour of my choice when they are hovered over. Kind regards Caroline