Hello, @Rivka,
Yes, we have many different fonts which inherit their sizes from the parent or from content zoom which is set from theme options.
More information about css variables you may find here = https://www.google.com/url?sa=t&source=web&rct=j&url=https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_custom_properties&ved=2ahUKEwjP3ZbDg7H8AhUA6LsIHTBBCsUQFnoECAkQAQ&usg=AOvVaw38JE6kCoqpUzRxloL2znq9
Regards