An ipv4-to-ipv6 transition mechanism with native support for network address translation (nat) is called:

The answer is "Teredo".

Explanation:

Teredo is a technology for the transfer of the complete IPv6-enabled hosts, that are IPv4-based but, have no native IPv6 network connections. Teredo is an Internet switch, it was confusing because there is no reputation-based explanation.

It is a temporary measure, the Long-term use of native Internet connectivity should be made for all IPv6 hosts. It is also known as a network protocol, that is used to establish client/server communication, and it facilitates connectivity between devices that are behind NAT routers.

Both shades should be exactly the same

"computer screen desktop"? what? that phrase makes no sense, and it has nothing to do with modifying system components i assure you.