Css 3

Learn about Cascading Style Sheets LACUNY Web Management Roundtable October 21, 2005 http://www.lehman.edu/provost/library/CSS/CSS.ppt

CSS Separate Style From Structure of a Web Page • Specify point size and font of text; • Set margins within a web page; • Create a distinctive style for individual web pages or sets of web pages; • Format style to one element of a web page or to a numerous pages; • Control color of different elements of a web page; • Etc. October 21, 2005

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Font Appearance of an Element • HTML code

SPECIAL COLLECTION

• CSS rule H3 { Font-family: times new roman, 'serif'; Color: #800000; Text-align: center; }

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Understanding Style Rules • The style characteristics for an HTML element are expressed by Style Rules . • A set of style rules is called a Style Sheet. Sheet • Style rules are contained in the <STYLE> element in the document’s section. <Style type=“text/css”> P {color:blue; font-size: 24pt;} October 21, 2005

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Understanding Style Rules • A Style Rule is composed of two parts: a selector and a declaration. Selector

Declaration

TH {color: red;}. • The Selector indicates the element to which the rule is applied. • The Declaration determines the property values of a selector. October 21, 2005

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Understanding Style Rules • The Property specifies a characteristic, such as color, font-family, position, and is followed by a colon (:). • The Value expresses specification of a property, such as red for color, arial for font family, 12 pt for font-size, and is followed by a semicolon (;). Property

Value

P {color: red;} October 21, 2005

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Using the <STYLE> Element • The <STYLE> element is always positioned in the section of the document. • The <STYLE> element always contains attribute. The value “text/css” defines the style language as Cascading Style Sheets. <Style type=“text/css”> P {color:blue; font-size: 24pt;} October 21, 2005

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Using External Style Sheet • Style Rules can be expressed in an external Style Sheet - a text document that doesn’t contain any HTML code. There is no <STYLE> element in an external style sheet. • External Style Sheet has a .css extension. http://www.lehman.edu/provost/library/CSS/style_1.htm h1, h2, h3 {font-family: verdana, arial, 'sans serif'; color: #9933FF; text-align: center;} October 21, 2005

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Linking to an External Style Sheet • To link a Web page to an external style sheet a element should be added within element of a document with the URL to a style sheet. It tells the browser to find a specified style sheet. <Title>Demo_1 <Style type=“text/css”> October 21, 2005

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Linking to an External Style Sheet HREF attribute states the relative URL to the style sheet

The REL attribute describes the relationship between the current document and the document identified by the href attribute

<Title>Demo_1 <Style type=“text/css”>

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Using the Class Attribute Selector • CLASS is an HTML attribute that assigns a class name to any HTML element on a Web page. • Can be used to identify which style sheet rules should be applied for the particular element of a Web page Element

Class Selector

A.nav:link {color:#FF3300; text-decoration: none;} October 21, 2005

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Using the Class Attribute Selector • A class name is created by declaring a style rule and adding (.) flag character indicating that the selector is a class selector. A.nav:link {color:#FF3300; text-decoration: none;}

• Add it to HTML code of a Web page by using the CLASS attribute. ERIC October 21, 2005

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Example 1 http://www.lehman.edu/provost/library/CSS/demo_1.htm CSS Style Sheet http://www.lehman.edu/provost/library/CSS/style_1.htm

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Example 2 http://www.lehman.edu/provost/library/CSS/demo_2.htm CSS Style Sheet http://www.lehman.edu/provost/library/CSS/style_2.htm

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Example 3 http://www.lehman.edu/provost/library/CSS/demo_3.htm CSS Style Sheet http://www.lehman.edu/provost/library/CSS/style_3.htm

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Lehman College Library Web Site http://www.lehman.edu/provost/library// http://www.lehman.edu/provost/library/CSS/style.htm

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Lehman College Library Web Site CSS A.nav:link { color: #990000; font-size: 12px; line-height: 14px; font-family: arial, verdana, geneva, helvetica; text-decoration: none; } A.nav:visited { color: #CC3333; font-size: 12px; line-height: 14px; fontfamily: arial, verdana, geneva, helvetica; text-decoration: none; }

HTML In the element In the element Check your Lehman e-mail account October 21, 2005

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Useful Resources • Schengili-Roberts, Keith. Core CSS Cascading Style Sheets. 2nd ed. Upper Saddle River, NJ: Prentice Hall PTR, 2004. • Sklar, Joel. Designing Web Pages with Cascading Style Sheets. Course Technology, Incorporated, 2001. • W3C http://www.w3.org/Style/CSS/ • WDG Web Design Group October 21, 2005

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