Increasing font size limit

Hi,

One of the complaints I’ve received on one of my websites (https://chrisgrigorov.com) is that the Real Accessibility plugin does not increase the size of the font enough.

When clicking the increase font size button a few times it stops increasing the font size at some point, but the font is still not large enough for people with severe sight problems.
I’m using the Twenty Twenty-One WordPress theme. Might this be because it has reached the maximum font size allowed by the theme?

I’m still new to programming, but I’ve looked through the code and in the real-accessability.js file I’ve found this section:

// Make font bigger
function increaseFont() {
if(obj.fontSize < 3) {
showLoader(function() {
obj.fontSize++;
$(settings.markup).not(settings.exclude).each(function() {
var fontSize = parseInt( $(this).data(‘raofz’) );
$(this).css(‘font-size’, fontSize+(2*obj.fontSize));
});
});
}
}

Maybe I can fix it from here, but I really don’t know right now, because as I said I’m still new and learning to program especially with JavaScript.

Can you help me out with this? I want there to be no limit to how much the user can increase the font size?