you can do a preg_match for this.
you will have to read the css style into a string first. You could possibly do this with fread() or file() functions.
then have all the css "functions" in an array of individual strings.
Then the short hand code would be something like....
"check to see if my $css_string contains any of the following strings....
$font-size = "font-size";
$font-family="font-family";
if is does then
echo "<font ";
if($font-size){echo "size=12";}
echo ">";
###############
anyways, there's the shorthand of how the logic could be.
but to answer you question....yes it can be done with php.