Hello. the site has bad rendering font , thinner , and not much antialised, as Safari 6.0.5 has. See also the bold large fonts, the edge of the fonts.
I am not seeing anything on the home page that shows content being drawn onto transparent layers. I can only see the issue if I force the Mac to avoid LCD font smoothing altogether through System Preferences. Could you upload a screenshot of the portion of the page where you are seeing this issue?
No response in almost a year, closing. Please feel free to re-open if this is still an issue.