Cascading Style Sheets

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Cascading Style Sheets

• Patrick Lang
• Ammar Rahman
• Scott Schwartz
• Ashley Trexler

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What do they do?

• Cascading Style Sheets (CSS) are a way to
  separate the presentation from the structure of a
  web site.
• HTML was intended as just a  structural markup
  language and doesnt do a good job with the style
  of the page.

• The purpose of a CSS is to provide Web developers
  with a standard way to define, apply and manage
  sets of style characteristics.
• Font
• Color
• Size
• Background
• Margin indent
• Etc.

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How do they work?

• All you do is write a style, the way you want
  something on your page to look, in the style
  section of the Head. Give it a name, then using
  or surround the text in your body
  that you want to be that style.

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Cascading

• The "cascading" in Cascading Style Sheets refers
  to how property values are applied in the context
  of the parent/child hierarchy of the Web
  document.
• Child elements either inherit or override
  property values bound to their parent elements

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Style Sheet

• A style sheet is the encapsulation of style rules
  in a centralized location, either in the head
  section of the HTML document or in a separate
  linked file. The Web browser reads these styles
  and applies the specified formatting rules before
  displaying the content.

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Style Property

• If a value for a style property has not been
  specified for a child element but has been
  specified for its parent element, then the
  parent's value is used to display the element
• if the child element does specify a new value for
  a style property also specified by the parent,
  the browser uses the child's value to display the
  element.

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Example

• body
• font-family Verdana
• In the absence of any other instructions, the
  browser will display all textual elements using
  the Verdana font.

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Separating Style from Content

• What does CSS offer over pure HTML that would
  compensate for the additional complexity of using
  both?
• The primary benefit is the separation of style
  and content
• Does add some enhanced formatting and positioning
  features

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Separating Style from Content

• Empowers developers to create, use, and maintain
  standardized presentation rules without touching
  the content
• Separating style from content also makes code
  maintenance and reuse easier
• Can easily apply standard, professionally
  developed styles to newly published content
• No need for markup or formatting languages

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CSS Standards and Versions

• While the major browser vendorsMicrosoft and
  Netscapeeach offer implementations of CSS in
  their Web browser software, early implementations
  of CSS by these browsers have been generally
  incomplete, incompatible with one another, and
  buggy.
• W3C released the recommendation for CSS Level 1
• describes the foundation of the CSS language and
  syntax, and includes basic formatting
  functionality

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CSS Standards and Versions

• The current W3C standard is the recommendation
  for CSS Level 2
• CSS2 builds upon CSS1, adding support for style
  sheets that target particular mediums (such as
  printers), downloadable fonts, positioning, and
  tables
• CSS3 is currently under development by the W3C
  and attempts to formalize these extensions in a
  standard that captures common industry practice.

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Future Trends

• Contribute 3
• Contribute 3 is a significant evolution of the
  product, delivering substantial performance
  improvements, support for current Web-design
  techniques such as layouts based on Cascading
  Style Sheets (CSS)
• straightforward Web-page editor designed for
  maintaining existing Web sites

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Future Trends

• It enables users who don't necessarily build Web
  sites-administrative assistants, instructors, or
  marketing teams-to edit pages and add pages to an
  existing Web site, without any assistance from
  the Webmaster
• Offers Better Performance
• Contribute 3 retrieves and publishes pages
  significantly faster by caching many of the files
  that Contribute 2 transferred via FTP
• Cost is 50 more then Contribute 2

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Questions?