How to beat z-index?

Question

css

Hello, there are two parent blocks.
At the bottom there are tabs that, when adapted by absolute positioning, are raised up. At the top there is a drop-down list for choosing a language. The problem is that the dropdown is hidden under the bottom block because the parent has a higher z-index. If you make the lower z-index smaller, then its successors raised up hide under the upper block. I tried to fix it with opacity:.99 but it didn't work.
What can I do?
Website link
Thank you

Answer 1

Removed the z-index from the element with id=header. The drop-down list is no longer hidden, the rest of the elements are in their places.

Answer 2

You need to go to the site
As I understand it, the banal inline style on the menu z-index: 999999999999 !important; didn't fit?)