Squarespace Custom CSS Expert

PLEASE DO NOT BID ON THIS JOB IF YOU HAVEN'T ADDED CUSTOM FONTS TO SQUARESPACE BEFORE - ITS A WASTE OF YOUR TIME AND MINE. THIS WOULD BE AN EASY TASK FOR SOMEONE WHO KNOWS WHAT THEY ARE DOING.

General information for the website: Fashion Design
Kind of development: Customization of existing website
Num. of web pages/modules: 5
Description of every page/module: Hello,

I have designed a website for my client in Squarespace and I have hit a problem. I have added some custom CSS as the client wants ALL the fonts changed to Century Gothic - so body text in regular / headiings in bold including Title Font but it's not working.

The links to download both of these fonts are here:

Century Gothic Regular:
http://www.911fonts.com/font/download_CenturyGothicRegular_4365.htm

Century Gothic Bold:
http://www.911fonts.com/font/download_CenturyGothicBold_4637.htm

So I need someoby to repeat back to me what I need - PLEASE don't send generic copy and pasted links to your portfolio - I don't need to see those as this is basically just a swapping of fonts.
Description of requirements/features: I will send login details to the site to the bidder I accept.
Extra notes: