The difference between a trademark and a font size is:

1.

Legal basis

"Trademark Law of the People's Republic of China" Article 8

Any mark that can distinguish the goods of a natural person, legal person or other organization from the goods of others, including words, graphics, letters, numbers, three-dimensional signs, color combinations and sounds, etc., as well as the above Any combination of elements can be applied for registration as a trademark.

Article 54 of the "People's Republic of China and Civil Code"

A natural person engaged in industrial and commercial operations shall be an individual industrial and commercial household after being registered in accordance with the law. Individual industrial and commercial households can set up a font size.