<link> to a css file requires .css ???

Hello, I realize this is more of an html question than a php, but I was hoping someone here would know what's going on. I am linking to a stylesheet and it is requiring me to use *.css extension. I want to use a .php extension (and have the php engine generate css). However, whenever i use a .php extension the link tag does not seem to work. This works! <link rel="stylesheet" type="text/css" href="http://localhost:8080/some.css" /> This doesn't work but I don't understand why not??? <link rel="stylesheet" type="text/css" href="http://localhost:8080/some.php" /> The page http://localhost:8080/some.php displays the css exactly the same as http://localhost:8080/some.css Why can't I link to a css file by using a different extension? Thanks in advance, dK `