On a Linux server, I need to find all files with a certain file extension in the current directory and all sub-directories.

Previously, I have always using the following command:

find . -type f | grep -i *.php

However, it doesn't find hidden files, for example .myhiddenphpfile.php. The following finds the hidden php files, but not the non-hidden ones:

find . -type f | grep -i \.*.php

How can I find both the hidden and non-hidden php files in the same command?