main menu size variant

Hi I try Rife free before buy a pro version, since few days I customize the theme. Yesterday something changed and I can’t come back like the begening.

I use regular top menu (white), and before, when I was scroll, the menu change to black and reduce itself little.

Today it turn on black but not reduce. I added yesterday a shadow under the menu and I thinked it as linked, but now I desactivated shadow under the menu and the menu doesn’t reduce, The reduction of the size appear just when I scroll up.

I’m embassared because I don’t known what I changed more to affect this menu.

Thanks lot for your help ??

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