snippet places colours on web-page

Hi,

Firstly snippet cbt is a first rate plugin in my. I have used it to enable people to extract code from my website and it works brilliantly. Lately rather than code I wanted to display snippets that provide terminal window instructions such as sudo apt-get some package. When the snippet displays on my site certain words change color such as the -get is a differnt color to the apt. Is there a way to ensure that the snippet displays in white (DARK BACKGROUND). I have tried various themes and types but cannot stop the appearance of colours changing randomly.

Kind Regards
Anwar