change E-mail field size width

Hikashop latest version
Earlier I have done some modifications with the Hikashop checkout page and it all works great.
But I need to increase the sizes of the fields like name, adress, etc. For this I went to Hikashop->Display->Custom fields and changed the size of each filed.
But I can't find the e-mail field? Where is this field located. Please see attached image below to see what I mean.

I tried to use Firebug in order to figgure it out, but I can't find a solution.

Any advice ?

Hi,

I think that you'll be able to do that by using some CSS code, but I'll need a link to your page for more precision.

OK sorry for late reply.

I still have the same problem with the e-mail field size. Please click on attached link to my live site checkout page. (also see attached image)