Considering the following dialog, what does *pero de corazón* mean here?

> 
> **A**: Soy de España, claramente.  
> 
> **B**: Yo soy de España ***pero de corazón***.
> 
> 
> 

I'm very new to Spanish so when I found all the words in the dictionary, I ended up with "*but from heart*" so my first thought was "*I'm from Spain too but from the heart of it*". But now it seems doubtful to me that you can use "*corazón*" like that in Spanish because I couldn't find any similar examples.

So on second thought, I think it should be something like "*to tell you the truth*" or "*in fact*" because I found "*de corazón*" in the dictionary and it says "*sincerely*". But I'm just guessing from the context and I might be wrong. 

And what does ***pero*** mean then?