How to change the infobar background color in Safari on a smartphone?

This system infobar color is assigned automatically, but you can change this manually as well.

To do this, you need to add the T674 block from the "Other" category to the page.

This modifier block adds a background image for the whole page.

Add it to the page.

You can delete the image in the Content tab of the block.

Then go and select the full page background color in the block settings:

Save the changes and close the block settings.

Your smartphone's infobar will now use this specified color. 

Note that this setting will be applied to the whole page.

That is, blocks' background will change to this color if you have not specified another color for blocks manually.

Important: This option is available just for iPhone X and newer devices that use ios 15 and higher.