Cart icon color after scroll

Hi there, how are you?

I’m using transparent header and have the cart icon set to “Display floating on the side, but only once product was added to the cart”.

But once a product is added to the cart, the cart icon background turns to white (a white square), which makes the transparent menu look quite strange with a white square on it.

I managed to make the cart icon background transparent using css but as the icon itself is dark, it is quite hard to see it on the transparent header.

I also managed to make the icon itself white, so it is visible on the transparent header, but once I scroll down, it doesn’t change the color (it stays white), so I can’t see it on the menu background (which is white) after scroll.

So how can I have the cart icon background transparent with white icon and have the icon color changed after I scroll the page?

Thank you.