Why is my CSS3 Transition not working in Firefox?

Question

It's working elsewhere on the site using the same CSS as far as I can tell. It works in Chrome. Here is the full page: anthonyotislawrence.com

Here's the part that's not working:

<a class="socialBox linkedIn">
    <h3>LinkedIn</h3>
    <p>linkedin.com/anthonyotislawrence</p>
</a> 
<a class="socialBox facebook">
    <h3>Facebook</h3>
    <p>facebook.com/anthonyotislawrence</p>
</a>

and the CSS

.socialBox {
    display:block;
    min-width:200px;
    padding:4px 0 4px 55px;
    height:40px;
    line-height:20px;
    background-repeat:no-repeat;
    background-position:left center;
    position:relative;
    -webkit-transition: all .5s ease-out;
    -moz-transition: all .5s ease-out;
    transition: all .5s ease-out;
    text-decoration:none;
    margin:30px 0;
}
.socialBox.linkedIn {
    background-image:url(../images/linkedin.png);
}
.socialBox.facebook {
    background-image:url(../images/facebook.png);
}
.socialBox:hover {
    left:15px;
    cursor:pointer;
}
.socialBox:hover p {
    text-decoration:underline;
}

Answer 1

It looks like FF wont transition default values. They have to be declared on the original element before it will transition to the new properties.

Answer 2

I had an issue similar to the OP where my transitions worked in every browser except Firefox. In my case I had intervals of zero seconds. I used just a 0 and not 0s. This caused the transition to not work at all in Firefox. I don't think this was the issue for the OP but posting here in case it helps someone else.

This does not work in Firefox:

top 0 linear 1s

This works:

top 0s linear 1s