font size em responsive code example
Example 1: responsive font-size
/* please refer to https://developer.mozilla.org/fr/docs/Web/CSS/clamp() */
font-size: clamp(40px, 10vw, 70px); /* clamp(MIN, VAL, MAX) */
Example 2: how to make font responsive
html { font-size: calc(1em + 1vw); }