CSS Page

File1:CSS.page

<apex:page cache="true" showHeader="false" contentType="text/css">
body  {
    -x-system-font: none;
    background: #E3E3E3 none repeat scroll 0 0;
    font-size-adjust: none;
    font-stretch: normal;
    font-style: normal;
    font-variant: normal;
    font-weight: normal;
}
body, h1, h2, h3, h4, h5, h6, hr12, hb12  {
    font-family: Arial, Helvetica, sans-serif;
}
</apex:page>

File2:VF_Page

<apex:page controller="CatalogCtl" sidebar="false">
<apex:stylesheet value="{!$Page.CSS}" />

</apex:page>