Jquery Mobile Custom CSS Help

General information for the website: n/a
Description of requirements/features: I need fast assistance with what should be a really simple problem but I have spent literally a whole day trying different things and I am ready to explode!

All I want is for someone to do / show me how to made icons bigger in the footer navbar element of a Jquery Mobile website as the standard 16 x 16 pixels is far too small. I want to use custom icons which I can design myself with no problem but can't figure out how to get them to work and I have literally Googled this issue to death.

I can't imagine this taking any longer than 10 minutes for the right person.

Please be aware I am using a custom theme (from Themeroller) and I expect the person to do sort the issue not just provide a line of code and actually tell me how to do it for the future.

This is needed really urgently
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