JS runs on the client. Perl runs on the server (in this setup, anyhow). JS starts working only after Perl has done all its work generating the page to send to the browser. So, in a way, the JS folks are right.

But what you *can* do is go through a JS-enabled page which creates a link (or, perhaps, a form submit button) that adds the JS-only info via GET or POST to the server. Alternately, use JS to set a cookie on the passthru page and have your Perl scripts read the cookie. Subsequent Perl-generated pages can act on this information.

Limitation: need for a passthru page, and if the user resizes her browser after the information is passed, she'll be stuck with your CSS-defined values.

sample code:

<script type='text/javascript'>
 <!--
    // I don't know which property we're talking about
    // so this is schematic
    document.writeln('<input type="hidden" name="xsize" value=window.x
+size>');
    //blah blah
 // -->
 <input type="submit" value="Enter the Site">
</form>
[download]

HTH, although I in no way endorse your obsession with controlling presentation to this degree =)

Philosophy can be made out of anything. Or less -- Jerry A. Fodor