Thank You kovidgoyal!
I've never heard about recipes before, but in the last days I read a lot about them. I see it's very complicated to read news with an e-Book Reader yet. :/
I can now change my font size with:
conversion_options = {'base_font_size' : ##}
Your suggestion don't have any effect
conversion_options = {'font_size_mapping': ##}
But I'm not able to change different sizes individualy like:
Font size key : 7, 8, 10, 12, 14, 16, 18, 20
If I increase all font sizes in the same manner I get monstrous headlines.
Thanks!