import font-family

I  have tried to add a project font (under File > Project Settings > Font List.

I can add the font family name but I am unable to add the import for the font e.g. 

.font-family-roboto {
font-family: Roboto, 'Franklin Gothic Medium', Tahoma, sans-serif;
font-weight: 300;
font-size: 1.25em;
}

Along with the @1552174:

@1552174 url('https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swap');

I have included in the projects default.css, but unable to add for project settings.

Regards Rich