Child style sheet not fully working

Very strange problem.

I created a child theme as I have a fair number of css changes and prefer them to be in a style-sheet. Got it all working perfectly. But then one day certain parts of the css to do with woocommerce cart were not working. Checked my style-sheet which was correct. Uploaded it again and it once again worked. Dismissed it thinking it was me.

But then it happened again. Uploaded css file again and all was good again.

Now, after updating Kadence parent yesterday, the css to do with the product options default colour is not working. My site colour default is white as I have a black background, the default option (Choose Options) is white (so invisible) until you click on it, so my css changes it to black but that bit is not working.

I uploaded style-sheet again but this time it didn’t rectify the problem.

If I put the code into Customise > Additional CSS it works so I know the code is correct; besides which it WAS working.

It is only that part of the style-sheet that is not working, the rest is.

The page I need help with: [log in to see the link]