Changing the clour and border lines on invoices

Hi. How can I change the table border line thickness on the printed invoices? At the moment these do not show up on the print-outs. Also changing the colour of the table title and margins would be great. Thanks.

modify : mail > orders > Invoice.tpl





example for cadre




{hook name="orders:invoice_company_info"}

lucien

a1.gif

The location of the file is:

\var\skins\basic\mail\orders\Invoice.tpl



On line 20 i changed the wide from 602px t0 720px




and on line 206 i added border 1.