Google will be soon adding the Dark Theme for the feed section for Pixel and non-Pixel phones. Currently, the Pixel users are used to the dark theme in the background for Pixel Launcher, app list, Quick Settings, and the Google Feed. But, the theme is completely dependent on the wallpaper and is not available for the entire interface. We are expecting the feature soon as Google is testing it out.
On Reddit, users have posted pics that shows a proper dark theme with white text on dark gray cards. There are shadows visible on the side of the cards and you can still see the dark text on a white background for the weather card. However, the background is still transparent and we cannot predict much because of the ongoing development stages.
The Dark Theme will also apply on non-Pixel devices as we can see the search pill on the top of the feed. At the moment, it is still unclear where the theme settings will appear, if it would be under Device theme toggle or any Google App.
Google has been adding the dark look to many Apps recently like YouTube, which features both Light and Dark mode. Also, we see the dark theme with the Android Messages App that also comes with the Google Material Theme.
Notably, Android 9 Pie will be introducing the new feature that gives Pixel phone the power to have a system-level Device Theme. This won’t depend on specific wallpapers and Google will be bringing this feature on all Pixel devices in the future release.