How to write .htaccess rewrite rule based on client IP?

Question

Apache HTTP Server

The task is quite natural: to block access to the site (a special domain allocated to developers for testing purposes) to everyone except for a certain IP. It would seem, what could be easier?

order deny,allow
deny from all
allow from allowed.ip.address

But I want to make it a little more beautiful, namely, not just give the left-handed visitors a thrashing, but show them a specially designed page with the project logo and a description of the situation. Those. in principle, this is allow plus one rewrite for just one specific. For any IP, its own set of rewrite rules must operate.
Tell?

Answer 1

To redirect all those who are not destined to get to the site, then:
Give access to files to someone who is lucky enough to visit the site:

<FilesMatch "^(file1|file2)\.html$">
    allow from allowed.ip.address
</FilesMatch>

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