[support] code block style

Hi, I've just started setting up my own website http://www.linuxcrusaders.org with drupal 7 where I'm trying to post various linux tips and code as I go along. I would like the code blocks to appear with a black background and green foreground (like a terminal). I tried the geshiphp module, though I'm not sure this will accomplish it, and besides which it doesn't seem to be quite ready for drupal 7 yet. Therefore, I wondered if anyone could recommend another way of achieving this, perhaps editing the css stylesheet. I'm not sure if this is also relevant, but I am using the Mayo theme. Thanks for any help. Ed.