CSS: Separating Design and Content Kevin Campbell Duke University/Grouchyboy.com

Assumptions  You know HTML  You do not know CSS  You care about aesthetics and function  You have 50 minutes to kill

What We’ll Do  What is CSS?  View some code and talk basics  Why use CSS? Advantages to Workflow Cost Savings  Implementations  Resources

What are Cascading Style Sheets?  Created by Hakon Wium Lie of MIT in 1994  Has become the W3C standard for controlling visual presentation of web pages  Separates design elements from structural logic  You get control and maintain the integrity of your data

Let’s See Some Code  Sample Style sheet Sample Style sheet  Rule Structure

Selectors  Element Selectors – (refer to HTML tags) H1 {color: purple;} H1, H2, P {color: purple;}  Contextual – (refer to HTML, but in context) LI B {color: purple;}

Selectors  Class Selectors Danger! Be careful… ……. In your HTML code - H1.warning {color: red;} OR to an entire class….warning {color:red;}

Applying CSS to HTML  Style rules can be applied in 3 ways: Inline Styles: A large purple Heading For individual elements using the STYLE attribute Embedded style sheets: Stylin’! H1 {color: purple;} P {font-size: 10pt; color: gray;} … External style sheets: <LINK REL=stylesheet” TYPE=“text/css” HREF=“styles/mystyles.css”> This is true “separation” of style and content. Keeping all your styles in an external document is simpler

Why CSS?  Advantages to Workflow  Cost Savings  You WILL Be Cooler

Advantages of CSS  Workflow Faster downloads Streamlined site maintenance Global control of design attributes Precise control (Advanced)  Positioning  Fluid layouts

Advantages of CSS - Cost Savings  Cost Savings Reduced Bandwidth Costs  One style sheet called and cached Higher Search Engine Rankings  Cleaner code is easier for search engines to index  Greater density of indexable content

Advantages of CSS - Cost Savings  Faster download = better usability Web usability redesign can increase the sales/conversion rate by 100% (source: Jakob Nielson)Jakob Nielson CSS requires less code Tables require spacer images Entire table has to render before content CSS can control the order that elements download (content before images)

Advantages of CSS - Cost Savings  Increased Reach CSS website is compatible w/ many different devices In 2008 an est. 58 Million PDA’s will be sold (Source: eTForecast.com) 1/3 of the world’s population will own a wireless device by 2010

Implementations  Apply to HTML pages  Apply to dynamic data Format or style XML  Use for layout (this is cool) See

CSS isn’t perfect (yet)  CSS support in browsers is still uneven  Make sure your CSS properties are supported

Resources  This is CSS at its finest  The Official CSS Site  Australian firm, very professional  monkey/reference/stylesheet_guide monkey/reference/stylesheet_guide Where I learned CSS and Web Design

Come and see me at 3:30pm!  “Making Your Web Site More Appealing”