CSS Code works in Firefox and Internet Explorer 9, but not in Safari or IE 8 or <

The Website is here: http://pflugervillefire.org/Living%20Safe%20and%20Well%20Expo

The issue is that I'm using a CSS style to offset the text over the picture. It works fine in Firefox and IE9, but not lesser versions of IE or Safari on my Iphone.

I inserted the following code in the heading of the page, and in the theme's .css file, and have turned CSS aggregation on in the performance section of my administration site.

Any ideas on what's going on?