Theme customization not working

I try to style the elements as seen in the guide: https://github.com/hbb20/CountryCodePickerProject/wiki/CCP-Theme-Customization
but nothing work, not programically or in the XML. Just trying to change the text size or color, but no change. I can change the arrow size.

Start with the linked CCP Theme Customization guide and reproduce the reported XML and programmatic styling attempts for text size and color. Compare those results with the arrow-size customization that works; done means the documented text styling changes are visibly applied, but the issue names no source files or tests to inspect.

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