CSS can be specific to the type of media being used to view the web page. So, for example, it is possible to have some styles that only apply when a page is printed and others that only apply on-screen. It is possible to include CSS specific to a media using the following pattern:
<STYLE type="text/css"> @media print { BODY {font-size: 10pt; background: white;} } @media screen { BODY {font-size: medium;} } </STYLE>