Where is stylesheet url defined

In this example, three style sheets are combined into one "Contemporary" style that is applied as a preferred style sheet.

To combine multiple style sheets into a single style, one must use the same TITLE with each style sheet. An external style sheet is ideal when the style is applied to numerous pages.

With an external style sheet, an author could change the look of an entire site by simply changing one file. As well, most browsers will cache an external style sheet, thus avoiding a delay in page presentation once the style sheet is cached. Very old browsers such as Netscape 2. This use of comment tokens to hide the style sheet from old browsers should only be used in HTML , where the comment tokens are actually part of the style sheet.

An embedded style sheet should be used when a single document has a unique style. If the same style sheet is used in multiple documents, then an external style sheet would be more appropriate. A style sheet may be imported with CSS's import statement. Any rules specified in the style sheet itself override conflicting rules in the imported style sheets.

The order in which the style sheets are imported is important in determining how they cascade. In the above example, if the style. Imported style sheets are useful for purposes of modularity. For example, a site may separate different style sheets by the selectors used. There may be a simple. In addition, there may be an extra.

A tables. These three style sheets could be included in HTML documents, as needed, with the import statement. The url CSS function is used to include a file. The url function can be passed as a parameter of another CSS functions, like the attr function. Depending on the property for which it is a value, the resource sought can be an image, font, or a stylesheet.

A URI identifies a resource. This specification does not specify how style sheets from different style languages cascade. Authors should avoid mixing style sheet languages. In the following example, we specify two alternate style sheets named "compact". If the user selects the "compact" style, the user agent must apply both external style sheets, as well as the persistent "common. If the user selects the "big print" style, only the alternate style sheet "bigprint. A cascade may include style sheets applicable to different media.

The user agent is then responsible for filtering out those style sheets that do not apply to the current medium. In the following example, we define a cascade where the "corporate" style sheet is provided in several versions: one suited to printing, one for screen use and one for speech-based browsers useful, say, when reading email in the car.

The "techreport" stylesheet applies to all media. The color rule defined by the STYLE element is used for print and screen but not for aural rendering. When the user agent wants to render a document, it needs to find values for style properties, e. The exact mechanism depends on the style sheet language, but the following description is generally applicable:.

The cascading mechanism is used when a number of style rules all apply directly to an element. The mechanism allows the user agent to sort the rules by specificity, to determine which rule to apply. If no rule can be found, the next step depends on whether the style property can be inherited or not. Not all properties can be inherited. For these properties the style sheet language provides default values for use when there are no explicit rules for a particular element.

If the property can be inherited, the user agent examines the immediately enclosing element to see if a rule applies to that.

This process continues until an applicable rule is found. This mechanism allows style sheets to be specified compactly. Some style sheet languages support syntax intended to allow authors to hide the content of STYLE elements from non-conforming user agents. This example illustrates for CSS how to comment out the content of STYLE elements to ensure that older, non-conforming user agents will not render them as text.

This section only applies to user agents conforming to versions of HTTP that define a Link header field. Note that HTTP 1. Web server managers may find it convenient to configure a server so that a style sheet will be applied to a group of pages.

For instance,. It is possible to specify several alternate styles using multiple Link headers, and then use the rel attribute to determine the default style. In the following example, "compact" is applied by default since it omits the "alternate" keyword for the rel attribute.

This should also work when HTML documents are sent by email. Some email agents can alter the ordering of [RFC] headers. To protect against this affecting the cascading order for style sheets specified by Link headers, authors can use header concatenation to merge several instances of the same header field.

The quote marks are only needed when the attribute values include whitespace. Use SGML entities to reference characters that are otherwise not permitted within HTTP or email headers, or that are likely to be affected by transit through gateways. This CSS example sets color and font size information for the text in a specific paragraph. In CSS, property declarations have the form "name : value" and are separated by a semi-colon. The style sheet language is specified as a content type e.

Authors must supply a value for this attribute; there is no default value for this attribute. It may be a single media descriptor or a comma-separated list. The default value for this attribute is "screen".

Attributes defined elsewhere lang language information , dir text direction title element title.