In this case, I think your best bet is using the custom theme variables/properties that are built-in and ready to go. They can be found in the link and also in the app.css
file in the developer tools.
The inline title picks up the --h1-font
value by default, but I added that in (commented out) for if you want to change it later. Give this a try:
body {
/* --inline-title-font: var(--h1-font); */
--h1-font: Georgia;
--h2-font: Georgia;
--h3-font: Georgia;
--h4-font: Georgia;
--h5-font: Georgia;
--h6-font: Georgia;
}
Have a good look over this post as well: