To change Add ons product font, from this.
to something like this.
You can use this code to Custom CSS.
@font-face {
font-family: 'Gotham Regular';
src: url(https://static1.squarespace.com/static/6672ecf757a5d945cabc3965/t/667cd600ab3a1e53ea8a43f6/1719457280881/GothamCond-Black.ttf)
}
section.product-add-ons * {
font-family: 'Gotham Regular' !important;
}


