A new search results page design has begun rolling out for Google that has the rounded search bar that sticks to the top of the page as you scroll through the search results. This new design began testing by Google back in August and is now rolling it out to all searchers.
The biggest difference between the old and new search bar header is that the new one now sticks to the top of the search results page as you scroll down to see more search results. The old design didn’t do that. In order to access the search bar, you had to scroll all the way back up to the top of the page.
The other difference is the search bar is no longer a box, it is now rounded.
Here is how it looks when you scroll down the page:
This design is currently only on desktop search results. This does not function on mobile search results.