Problem with the text and description on the top of photos

<!– sorry for my bad english! –>

Hi,

I’m currently making a blog using autofocus.

I’ve translated it in french, and there was no problem.

But when I go over an image with my mouse on the home page, the title and the description don’t appear.

I have this problem only when I use firefox, there is no problem with google chrome or opera.

I tried disabling all plugins but it didn’t resolved the problem.

Did I do something wrong?

the blog is located here

Thanks.