Very often Web creators are using an external style sheet, or a style element to add style information to their html pages. By doing, we specify what is the style language used in the Web page. For example using the `link` element.
<link href="cute.css" rel="stylesheet" type="text/css"/>
But if your page is using the
style attribute, the user agent may not know what is the language used for styling. This is a principle of orthogonality. A company could launch a user agent with a new style language and a new mime-type. It will be difficult to impose and ensure interoperability because of the deployment base, but it is still possible.
If you want to set up a default style sheet language for your Web site, there are a few choices. You can use a meta name in each of your page:
<meta http-equiv="Content-Style-Type" content="text/css"/>
or you can specify an HTTP header:
SetEnvIf response Content-Type html-content=1 Header add "Content-Style-Type: text/css" env=html-content
PS: mod_headers and mod_setenvif are not activated in the base configuration of Apache httpd, you have to activate them.
Examples given for xhtml documents served as