problem front end manager and a general img tag

Hi,

just found out following issue, check the image in this post (not related to that issue)
http://modxcms.com/forums/index.php/topic,43210.0.html

So the QM gray bar more or less exploded and the green image left from the edit resource button was covering the entire screen. Found out it was a problem with the following general style i set in my CSS


Just took it out and all is fine, but should this behavior arise with this style declaration?

Frank.