Is there a way to link in a stylesheet where the extension is not css

Question

When I dynamically connect in the CSS (and JS, if you know—I haven't tested) the browser doesn't render the styles, what should I do?

Here is my code:

<link rel="stylesheet" href="css/test"/>

If I manually upload and save the file as test.css it then works.

<link rel="stylesheet" href="css/test.css"/>

Is there a way to say to the browser, "This is a CSS file? Please disregard that it doesn't have a CSS extension"?

MORE

The reason is that I'm setting up a server that enables users to dynamically design their own CSS. I don't want to create a tangible (digital) file every time a user updates the CSS or a new user opens their account because I'm saving this information in a database.