Here's an example - over the name appears gray, which is not in all browsers on Windows. Where the text of the greeting - there's not a lot lighter grayness, it is so necessary, and here under it...
For MacBook - grey. Why and how to solve it?
Complement a link to the Page
Separately from the code where the problem can not be due to the fact that you do not understand where could be the problem. Seems to interfere with bg transparent, but I've removed it, and the greyness is still there.