What is CSS ?
CSS ( Cascading Style Sheet , cascading style sheets) by the W3C (World Wide Web Consortium) of CSS to create and maintain a work group. It is a compilation does not need to be labeled language directly from the browser to execute, to control the Web appearance of the page. By using the CSS control page style attributes of each element of the display, the page content may be separated from the forms.
CSS History
CSS1 as a W3C recommendation, CSS1 released in 1996 Nian 12 Yue 17 days. 1999 Nian 1 Yue 11 days, this recommendation is to be revised.
CSS2 as a W3C recommendation, CSS2 released in 1999 Nian 1 Yue 11 days. CSS2 adds support for media (printers and aural devices) and downloadable fonts.
CSS3 plans CSS into smaller modules.
CSS advantage
1 to avoid the unnecessary use of HTML code to reduce the code amount.
2 shorten the time to update and maintain
3 to make HTML effects can not be achieved
CSS preparation of specifications
Selector ( Selector ): The so-called selectors are rules for selecting the document you want to apply those elements of style. The element may be ( X- ) the HTML of a label, or may be specified in the page class (class) or id attribute defined tag.
Disclaimer: statement contained in "a pair of braces } { " inside, to tell the browser how to render objects on the page and select the character to match. Internal declared attributes and their values by the composition, and separated by a colon, a semicolon end, a declaration may be a combination of one or more attributes.
Property ( Property ): property by the official CSS specifications agreed upon, rather than custom browser other than individual private property in addition.
Attribute value ( value ): value of the attribute names and the attribute is placed behind the colon, following the specific content category attribute presented in different forms, including a general value, and a unit key.
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