Another excellent case for the judicious use of pre tags is Saturn.

Personally, I've found adding the following to my On-Site CSS Markup is quite helpful in determing at a glance whether pre tags are the problem:

/* Adjust pre/code font, size */
pre { color: MediumAquaMarine }
pre.code.c { font-size: 12pt; font-family: consolas; color: LightSteel
+Blue }
tt.codetext { font-size: 12pt; font-family: consolas; color: LightStee
+lBlue }
tt.inlinecode { font-size: 12pt; font-family: consolas; color: LightSt
+eelBlue }
[download]

Doubtless other Monks will want to adapt this to their own needs and preferences (for one thing, I need a large font because I am visually impaired).

HTH,