Google is testing the dark theme again for its search page. The last time users reported seeing a dark theme was last month.
The dark theme of the world’s most visited page will follow your favorite Windows or macOS theme. If you’ve set yours to Light, Google search will remain unchanged, set it to Dark, and you’ll be greeted with the new Dark theme.

The dark theme doesn’t make the background completely black, but rather a very dark gray. The text has changed from black to white while the links seemingly remain blue.
Google is still in the A / B testing phase, so you may not have the change available yet. Once you do, Google search will greet you with a message on the new dark theme with the option to turn it on or continue as usual. There is no word when the dark theme will transfer to your mobile browser search.

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