I believe all browsers will show your site but perhaps just not correctly. Try having a look at this site; http://techpatterns.com/downloads/php_browser_detection.php It's probably got what you're looking for.
Remove any unused/not_important effects and ensure that the effects left are implemented cross-browser way.
Many thanks. That's i was looking for. But i cannot understant what is a spot on my site where i must put that code? Could you explain me this please?
Test your site in all the different browsers, if you have any problems you can detect the browser and send different code depending on who is requesting.
Maintaining browser-specific content and designs would be a maintenance problem. We design for the lowest common denominator and stay away from browser-specific functionality. If you are developing an intranet and the client has control over the browser, you can design for the specific platform. Keep it simple, know the target browser(s), and move forward.