Forum Moderators: open
The partially-blind may need a 48px font size to be able to read their screen, and you should do nothing to stop them. And be aware that just because the font on the screen is large does not mean that the printer font settings are also that large -- Programs for the visually-impaired may adjust the screen and the printer individually, and your efforts to 'control the user' may interfere with this. The result may be a lost visitor.
HTML is designed to give display control to the user. If your page does not display with a wide range of screen sizes and font sizes, then that points to a shortcoming in your design and layout skills.
Sorry to be so blunt, but the screen belongs to your visitor, and not to you. Accept this and move on.
Best,
Jim
Gave up px exact layouts some years ago for that very reason...