Css3 can i

The next example reduces the vertical space separating an H1 and an H2 that immediately follows it:. The following rule is similar to the one in the previous example, except that it adds a class selector. CSS 2. Attribute values must be identifiers or strings. The case-sensitivity of attribute names and values in selectors depends on the document language. For example, the following attribute selector matches all H1 elements that specify the "title" attribute, whatever its value:.

In the following example, the selector matches all SPAN elements whose "class" attribute has exactly the value "example":. Multiple attribute selectors can be used to refer to several attributes of an element, or even several times to the same attribute.

Here, the selector matches all SPAN elements whose "hello" attribute has exactly the value "Cleveland" and whose "goodbye" attribute has exactly the value "Columbus":. The first selector will match, for example, the value "copyright copyleft copyeditor" for the "rel" attribute. The following rule hides all elements for which the value of the "lang" attribute is "fr" i. The following rule will match for values of the "lang" attribute that begin with "en", including "en", "en-US", and "en-cockney":.

Similarly, the following aural style sheet rules allow a script to be read aloud in different voices for each role:. Matching takes place on attribute values in the document tree. Default attribute values may be defined in a DTD or elsewhere, but cannot always be selected by attribute selectors.

Style sheets should be designed so that they work even if the default values are not included in the document tree. More precisely, a UA may, but is not required to, read an "external subset" of the DTD but is required to look for default attribute values in the document's "internal subset.

Depending on the UA, a default attribute value defined in the external subset of the DTD might or might not appear in the document tree. Note that, typically, implementations choose to ignore external subsets. To catch all cases, the attribute selector for the default value must be dropped:. Care has to be taken that all property declarations that are to apply only to the default case are overridden in the non-default cases' style rules.

Thus, for HTML, div. The attribute value must immediately follow the "period". UAs may apply selectors using the period. One such example of namespace specific knowledge is the prose in the specification for a particular namespace e. Given these rules, the first H1 instance below would not have green text, while the second would:.

For example, the following rule matches any P element whose "class" attribute has been assigned a list of space-separated values that includes "pastoral" and "marine":. CSS gives so much power to the "class" attribute, that authors could conceivably design their own "document language" based on elements with almost no associated presentation such as DIV and SPAN in HTML and assigning style information through the "class" attribute.

Authors should avoid this practice since the structural elements of a document language often have recognized and accepted meanings and author-defined classes may not.

Note: If an element has multiple class attributes, their values must be concatenated with spaces between the values before searching for the class. As of this time the working group is not aware of any manner in which this situation can be reached, however, so this behavior is explicitly non-normative in this specification.

What makes attributes of type ID special is that no two such attributes can have the same value; whatever the document language, an ID attribute can be used to uniquely identify its element.

The ID attribute of a document language allows authors to assign an identifier to one element instance in the document tree. CSS ID selectors match an element instance based on its identifier. The UA may, e. In the following example, the style rule matches the element that has the ID value "z98y". The rule will thus match for the P element:. In the next example, however, the style rule will only match an H1 element that has an ID value of "z98y".

The rule will not match the P element in this example:. ID selectors have a higher specificity than attribute selectors. In XML 1. However, the cascading order of normal attribute selectors is different from ID selectors. It may be necessary to add an "!

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CSS3 Background-image options New properties to affect background images, including background-clip, background-origin and background-size CSS3 Border images Method of using images for borders CSS3 Border-radius rounded corners Method of making the border corners round. CSS3 Text-shadow Method of applying one or more shadow or blur effects to text CSS3 Transitions Simple method of animating certain properties of an element, with ability to define property, duration, delay and timing function.

CSS3 Box-sizing Method of specifying whether or not an element's borders and padding should be included in size units CSS3 Colors Method of describing colors using Hue, Saturation and Lightness hsl rather than just RGB, as well as allowing alpha-transparency with rgba and hsla. CSS3 Cursors original values CSS3 cursor values added in the spec, including none, context-menu, cell, vertical-text, alias, copy, no-drop, not-allowed, nesw-resize, nwse-resize, col-resize, row-resize and all-scroll.

CSS3 tab-size Method of customizing the width of the tab character. CSS3 font-kerning Controls the usage of the kerning information spacing between letters stored in the font. Navbar Vertical Navbar Horizontal Navbar.

Shadow Effects Box Shadow. Example p. Exercise: Set the background-color to red, of the first line of the paragraph. Report Error. Your message has been sent to W3Schools. W3Schools is optimized for learning and training. Examples might be simplified to improve reading and learning.