you can either change it in the sp theme… or add in the font resize plugin for sp… if you go the route of changing the css (editing the sp theme), be sure to create your own theme first to keep from losing changes… see: http://codex.simple-press.com/codex/themes/theme-basics/creating-a-theme/

Thanks Papa, I downloaded the font size plugin, installed it but I can’t see it, like a widget, or setting windown, where is it? 

I can’t see a place where I can work with it.

did you see: http://codex.simple-press.com/codex/plugins/our-plugins/available-plugins/font-resize/

I also assume you installed it as an sp plugin, not a wp plugin?

our provided themes should all include the necessary template functions for it to display…

I just noticed too that the Font Resizer seems to have disappeared. I am using the Default 1.2.2 theme. Font Resizer was installed via Simple Press plug-in upload. It used to be in the top right corner of my forum but no longer is.

Oh gosh – that IS a bug somewhere.
Apologies. I will open a ticket and look into it – and get to the bottom of it.

Just downloaded the update and all is well again with font resizing. Thanks so much.

Good to hear. Apologies for that. Good news is along with resolving he issue we also improved the way it is called!