Change font size on forms - Hyde Theme

Site URL: https://groundhog-wedge-akmr.squarespace.com/commission-orders

Hey all,

I am trying to work out how I can change the font-size on light-box forms on the site I'm working on. I understand it might rely on Custom CSS that caries depending on the Theme used (in my case, Hyde).

Any support on the code I should use would be greatly appreciated; also, it would be great to know how you worked it out so that I can increase the chance of answering my own questions in the future!

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oldbarnleather

Thanks in advance,

Jake