Custom title font?

So I found the css I needed to change in a closed topic but I’m having issues using my custom font.

So I’ve added the following replacing the names & domain of course

@font-face {
    font-family: 'YourFontName'; /*a name to be used later*/
    src: url('http://domain.com/fonts/font.ttf'); /*URL to font*/
}

then I modified the already existing title code from this

.basic #site-title a {
  font-family: 'Megrim', cursive;
}

to

.basic #site-title a {
  font-family: 'FontName', cursive;
}

From what I understand this should work but the results are odd. It completely ignores my custom font and uses comic san styled font.
I’m not sure what if anything i’m doing wrong. can anyone help me out?