modify the height of head bar

[zhh zhou <zhouzhh217 gmail com>]

Hello everyone, I want to change the height of head bar because it is really big for me. I can change the height of title bar by modify /usr/share/themes/Adwaita/metacity-1/metacity-theme-3.xml and found that 12px is just suitable. But I I really don't know how to change the height of head bar and the label bar marked on the picture. Can anyone tell me, thanks a lot.

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