I use the following CSS to make my fonts responsive:

Title 1

clamp(3rem, 2.5385rem + 2.0513vw, 4rem)

Title 2

clamp(2.4rem, 2.1231rem + 1.2308vw, 3rem)

Title 3

clamp(2.1rem, 1.9154rem + 0.8205vw, 2.5rem)

Title 4

clamp(1.8rem, 1.7077rem + 0.4103vw, 2rem)

Title 5

clamp(1.6rem, 1.5308rem + 0.3077vw, 1.75rem)

Title 6

clamp(1.4rem, 1.3538rem + 0.2051vw, 1.5rem)

Title 7

clamp(1.2rem, 1.1769rem + 0.1026vw, 1.25rem)

Subheading

1,2

Body

1

Body bold

1

Body big

1,125

Body small

0,875

This requires more than 4 fluid fonts, which I think is the maximum at the moment. Allow us to add any number of fluid fonts.