Change the Geek Masthead font

Just a general question to those of you who have a good handle on CSS. I would like to change the Masthead font to Times New Roman, Bold. I've tried some code in Custom.CSS in the template directory, but nothing changes. I won't pretend to know CSS code although changing the font should be easy enough. Maybe I'm putting the CSS code in the wrong place? Can anyone tell me where and what to change? Geek Masthead is perfect for what I need with the single exception of not being able to change the font.

Please give me your site url for checking, I'll help you to sort it out.

I placed Geek masthead on one of the pages of the website: marlboroughct.net/index.php/community
The masthead I'm trying to recreate is directly under geek masthead. Although I haven't tried it yet, I planned on putting the logo as a background image, which I'm assuming can be done without additional CSS.

Hi,
you can add the css code snippet below at the bottom of the templates/purity_iii/css/custom.css to custom style for texts on masthead

Thank you!! This is awesome. It works very well. The module is now 100% better than ever now that the fonts style/size can be changed.

Yes, we will add a feature what allows user can set font style for texts of masthead on the next version of Geek Masthead module.