Tiny, misaligned flags

Is there a way to increase the size (would be nice) and center the alignment (absolutely essential) of the flags on the language switcher in the header?

I’ve found a few snippets of code that supposedly fix this issue, but when I paste them into the CSS customizer, nothing happens. I love PolyLang and I’ve been using it forever, but I really need to get this straightened out.

Thanks!

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