Even though some may never have noticed it, on the homepage of Google.it or Google.com you can no longer change the background. Until a few years ago, you could put a personal image or a photograph of yourself in place of the white background of the search engine's home page.
The background on the search page is the best feature of Microsoft's Bing search engine. Try logging into Bing and discover the high definition photo which then changes every day.
If you want to keep using Google but you want to change the white background to a black one or a custom image, you can install aextension for Google Chrome and Firefox that allows change the background of the google home page.
The extension to install is Stylish and for the Chrome browser and also for Firefox.
Once Stylish is installed, you can download and install the Google Background script and immediately the Google home page will change background.
At that point, in the Stylish script page, you can press the Customize button to choose another ready-made background or to upload a custom image. Among the options you can also choose the font color and width.
If you only wanted to set the Google home page with a black background, in Dark Reader mode and in the options select the one to set the dark background only to the google.it site.
If you like to see wallpapers that change every day in rotation, I want to remember that you can rotate background images on Windows every day with Bing Desktop or with others programs to automatically change the PC desktop background