How to increase the textsize of HTMLtext proportional?

[Tiemo Hollmann TB]

Hello,

I give the user the option to change the textsize of all fields. No problem
so far by just changing the textsize and adjusting the field size. Now I
have a field with different textsizes in one field. Like bold and bigger
headlines, and standard text, etc.

How would you change the textsize of such a text by keeping the size
relation of the different chunks of text? Should I look up the HTMLtext and
manipulate every "font size attribute" - or is there a more straight forward
approach, I don't see?

Thanks

Tiemo