CSS: Text color cannot be distinguished between object, message, comment etc...

I am trying to make a simple readable GUI theme for my workshop using css but ".box_text" field line 270 is binded to all boxes (object, message, comment etc...) which is reducing the design a lot.

/* text inside boxes: message boxes, object boxes, graphs, comments, etc. */

So this kind of theme which avoid a lot of confusion between message and object boxes is not currently possible because it uses white text for boxes and black text for messages and comment: