CSS Tutorial

CSS Introduction

Wed Dec 03 22:25:33 +0000 2008

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Styles can be specified inside a single HTML element, inside the <head> element of an HTML page, or in an external CSS file. Even multiple external style sheets can be referenced inside a single HTML document.

CSS How to

Wed Dec 03 22:24:48 +0000 2008

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There are three ways of inserting a style sheet:

External Style Sheet
Each page must link to the style sheet using the <link> tag. The <link> tag goes inside the head section:
<head> <link rel="stylesheet" type="text/css" href="mystyle.css" /> </head>
Internal Style Sheet

You define internal styles in the head section by using the <style> tag, like this:

<head> <style type="text/css"> hr {color: sienna} p {margin-left: 20px} body {background-image: url("images/back40.gif")} </style> </head>

The browser will now read the style definitions, and format the document according to it.
Inline Styles

An inline style loses many of the advantages of style sheets by mixing content with presentation. Use this method sparingly, such as when a style is to be applied to a single occurrence of an element.

To use inline styles you use the style attribute in the relevant tag. The style attribute can contain any CSS property. The example shows how to change the color and the left margin of a paragraph:
Multiple Style Sheets

If some properties have been set for the same selector in different style sheets, the values will be inherited from the more specific style sheet.

For example, an external style sheet has these properties for the h3 selector:
h3 { color: red; text-align: left; font-size: 8pt }
And an internal style sheet has these properties for the h3 selector:
h3 { text-align: right; font-size: 20pt }
If the page with the internal style sheet also links to the external style sheet the properties for h3 will be:
color: red; text-align: right; font-size: 20pt
The color is inherited from the external style sheet and the text-alignment and the font-size is replaced by the internal style sheet.

CSS Syntax

Wed Dec 03 22:13:04 +0000 2008

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The CSS syntax is made up of three parts: a selector, a property and a value:
selector {property: value}
The CSS syntax is made up of three parts: a selector, a property and a value:
selector {property: value}
The selector is normally the HTML element/tag you wish to define, the property is the attribute you wish to change, and each property can take a value. The property and value are separated by a colon, and surrounded by curly braces:
body {color: black}
Note: If the value is multiple words, put quotes around the value:

p {font-family: "sans serif"}

Note: If you wish to specify more than one property, you must separate each property with a semicolon. The example below shows how to define a center aligned paragraph, with a red text color:
p {text-align:center;color:red}
All header elements will be displayed in green text color:
h1,h2,h3,h4,h5,h6 { color: green }
Say that you would like to have two types of paragraphs in your document: one right-aligned paragraph, and one center-aligned paragraph. Here is how you can do it with styles:
p.right {text-align: right} p.center {text-align: center}
You have to use the class attribute in your HTML document:
 This paragraph will be right-aligned. 

 This paragraph will be center-aligned. 
Note: To apply more than one class per given element, the syntax is:
 This is a paragraph. 
The paragraph above will be styled by the class "center" AND the class "bold".
You can also omit the tag name in the selector to define a style that will be used by all HTML elements that have a certain class. In the example below, all HTML elements with class="center" will be center-aligned:
.center {text-align: center}
The id Selector

You can also define styles for HTML elements with the id selector. The id selector is defined as a #.

The style rule below will match the element that has an id attribute with a value of "green":
#green {color: green}
The style rule below will match the p element that has an id with a value of "para1":
p#para1 { text-align: center; color: red }

CSS Tutorial

CSS Introduction

Cascading Order

CSS How to

External Style Sheet

Inline Styles

Multiple Style Sheets

CSS Syntax

The id Selector