Adding Caveat Brush to GP theme

Hi I've followed the support articles trying to add Caveat Brush Google Font to Generate Press theme but it's not showing up in list.
I'm using Simple CSS to add the code snippet
Have I got something wrong? Caveat only has one style being 400.
Below is the code I have entered

add_filter( 'generate_typography_customize_list', 'tu_add_google_fonts' );
function tu_add_google_fonts( $fonts ) {
$fonts['caveat_brush'] = array(
'name' => 'Caveat Brush',
'variants' => array('400'),
'category' => 'cursive'
);

return $fonts;
}