Adding Adobe Font to Dawn theme

Hi, I need to add an Adobe font to my website. I have added the “link ref” code just under the tag in theme.liquid:

I know I need to specify how to use the fonts using the code from adobe but I have no idea where to paste this code? Also how do i specify heading / body etc? This is the code I have:

HEADINGS:

font-family: din-2014, sans-serif;
font-weight: 700;
font-style: normal;

BODY:
font-family: din-2014, sans-serif;
font-weight: 400;
font-style: normal;

And do I need to add something like !important! after it somewhere to overrule the existing font code?

Thanks

This is what I have tried adding to the bottom of the base.cc file:

@font-face {
h1, h2, h3, h4, h5, h6, font-family: din-2014, sans-serif !important;
font-weight: 700;
font-style: normal;
}

{
body, p, font-family: din-2014, sans-serif !important;
font-weight: 400;
font-style: normal;
}

But it doesn’t work?