Adding Custom Font?

Hi guys - I’m hoping you can point me in the right direction, I’m attempting to add a custom font, but nothing seems to be working following the typical tutorials.

@font-face {
font-family: myFirstFont;
src: url(sansation_light.woff);

When I change the css to use the new custom font - it totally ignores it. Even removing the Yanone font from the list has no effect, so I know I’m missing something. Can you guys give me a little info on how you are using the Custom Yanone Kaffeesatz font?

Thank you!

Please ignore my idiocy. I was editing the mail theme vs. the child theme. My stupidity know no bounds =(