The fonts can be added in app/fonts folder.

After you done that you will need to specify in your css (app/style/scss/_vars.scss) the font’s family.

This is how the SCSS code should look like:

/* fonts */
$defaultFont: 'Open Sans', sans-serif;
$titleFont: 'Ubuntu', sans-serif;
$lato: 'Lato', sans-serif;
$glyph: Glyphicons Halflings;

The fonts are loaded in the header of each HTML file

<!-- Fonts -->

<link href="https://fonts.googleapis.com/css?family=Lato%7COpen+Sans%7CUbuntu:300,400,500,700" rel="stylesheet">