Concurring (in large part) with jethro, the css (for black text on transparent bg) would be:

<span style="color: black; background-color: transparent;">...<span>

Likewise, a decent css tutorial would rapidly (ca 2 hours effort, perhaps) take you well beyond blind experimentation with style sheets (and mention that colors can be specified in several ways, including, for example, hexidecimal values).

I'm quite sure, however, that the denizens of the Monastery are NOT uniformly ignorant of css; rather, presenting 168 lines of code, most of it utterly irrelevant to the issue you're facing, is a pretty good way to ensure that at least some Monks (/me included) will bypass your question in favor of others which demonstrate the virtue of brevity.