This tutorial has taught you how to create style sheets to control the style and layout of multiple web sites at once.

You have learned how to use CSS to add backgrounds, format text, add and format borders, and specify padding and margins of elements.

You have also learned how to position an element, control the visibility and size of an element, set the shape of an element, place an element behind another, and to add special effects to some selectors, like links.

For more information on CSS, please take a look at our CSS reference.

Now You Know CSS, What’s Next?

The next step is to learn XHTML and JavaScript.

XHTML

XHTML reformulates HTML 4.01 in XML.

If you want to learn more about XHTML, please visit our XHTML tutorial.

JavaScript

JavaScript can make your web site more dynamic.

A static web site is nice when you just want to show flat content, but a dynamic web site can react to events and allow user interaction.

JavaScript is the most popular scripting language on the internet and it works with all major browsers.

If you want to learn more about JavaScript, please visit our JavaScript tutorial.

Internet Explorer Behaviors

What is it? Internet Explorer 5 introduced behaviors. Behaviors are a way to add behaviors to HTML elements with the use of CSS styles.

Why avoid it? The behavior attribute is only supported by Internet Explorer.

What to use instead? Use JavaScript and the HTML DOM instead.

Example 1 – Mouseover Highlight

The following HTML file has a <style> element that defines a behavior for the <h1> element:

The XML document "behave.htc" is shown below:

Example 2 – Typewriter Simulation

The following HTML file has a <style> element that defines a behavior for elements with an id of "typing":

The XML document "typing.htc" is shown below:

It is possible to style HTML elements that have specific attributes, not just class and id.

Note: Internet Explorer 7 (and higher) supports attribute selectors only if a !DOCTYPE is specified. Attribute selection is NOT supported in IE6 and lower.

Attribute Selector

The example below styles all elements with a title attribute:

Attribute and Value Selector

The example below styles all elements with title="W3Schools":

Attribute and Value Selector – Multiple Values

The example below styles all elements with a title attribute that contains a specified value. This works even if the attribute has space separated values:

The example below styles all elements with a lang attribute that contains a specified value. This works even if the attribute has hyphen ( – ) separated values:

Styling Forms

The attribute selectors are particularly useful for styling forms without class or ID:

Media Types

Some CSS properties are only designed for a certain media. For example the "voice-family" property is designed for aural user agents. Some other properties can be used for different media types. For example, the "font-size" property can be used for both screen and print media, but perhaps with different values. A document usually needs a larger font-size on a screen than on paper, and sans-serif fonts are easier to read on the screen, while serif fonts are easier to read on paper.

The @media Rule

The @media rule allows different style rules for different media in the same style sheet.

The style in the example below tells the browser to display a 14 pixels Verdana font on the screen. But if the page is printed, it will be in a 10 pixels Times font. Notice that the font-weight is set to bold, both on screen and on paper:

See it yourself ! If you are using Mozilla/Firefox or IE 5+ and print this page, you will see that the paragraph under "Media Types" will be displayed in another font, and have a smaller font size than the rest of the text.

Different Media Types

Note: The media type names are not case-sensitive.

An image sprite is a collection of images put into a single image.

A web page with many images can take a long time to load and generates multiple server requests.

Using image sprites will reduce the number of server requests and save bandwidth.

Image Sprites – Simple Example

Instead of using three separate images, we use this single image ("img_navsprites.gif"):

With CSS, we can show just the part of the image we need.

In the following example the CSS specifies which part of the "img_navsprites.gif" image to show:

Example explained:

• <img class="home" src="img_trans.gif" /> – Only defines a small transparent image because the src attribute cannot be empty. The displayed image will be the background image we specify in CSS
• width:46px;height:44px; – Defines the portion of the image we want to use
• background:url(img_navsprites.gif) 0 0; – Defines the background image and its position (left 0px, top 0px)

This is the easiest way to use image sprites, now we want to expand it by using links and hover effects.

Image Sprites – Create a Navigation List

We want to use the sprite image ("img_navsprites.gif") to create a navigation list.

We will use an HTML list, because it can be a link and also supports a background image:

Example explained:

• #navlist{position:relative;} – position is set to relative to allow absolute positioning inside it
• #navlist li{margin:0;padding:0;list-style:none;position:absolute;top:0;} - margin and padding is set to 0, list-style is removed, and all list items are absolute positioned
• #navlist li, #navlist a{height:44px;display:block;} – the height of all the images are 44px

Now start to position and style for each specific part:

• #home{left:0px;width:46px;} – Positioned all the way to the left, and the width of the image is 46px
• #home{background:url(img_navsprites.gif) 0 0;} – Defines the background image and its position (left 0px, top 0px)
• #prev{left:63px;width:43px;} – Positioned 63px to the right (#home width 46px + some extra space between items), and the width is 43px.
• #prev{background:url(‘img_navsprites.gif’) -47px 0;} – Defines the background image 47px to the right (#home width 46px + 1px line divider)
• #next{left:129px;width:43px;}- Positioned 129px to the right (start of #prev is 63px + #prev width 43px + extra space), and the width is 43px.
• #next{background:url(‘img_navsprites.gif’) no-repeat -91px 0;} – Defines the background image 91px to the right (#home width 46px + 1px line divider + #prev width 43px + 1px line divider )

Image Sprites – Hover Effect

Now we want to add a hover effect to our navigation list.

Our new image ("img_navsprites_hover.gif") contains three navigation images and three images to use for hover effects:

Because this is one single image, and not six separate files, there will be no loading delay when a user hovers over the image.

We only add three lines of code to add the hover effect:

Example explained:

• Since the list item contains a link, we can use the :hover pseudo-class
• #home a:hover{background: transparent url(img_navsprites_hover.gif) 0 -45px;} – For all three hover images we specify the same background position,  only 45px further down.

Note: This is not yet a CSS standard. However, it works in all modern browsers, and is a part of the W3C CSS 3 recommendation.

Example 1 – Creating a Transparent Image

First we will show you how to create a transparent image with CSS.

Regular image:

The same image with transparency:

Look at the following source code:

Firefox uses the property opacity:x for transparency, while IE uses filter:alpha(opacity=x).

Tip: The CSS3 syntax for transparency is opacity:x.

In Firefox (opacity:x) x can be a value from 0.0 – 1.0. A lower value makes the element more transparent.

In IE (filter:alpha(opacity=x)) x can be a value from 0 – 100. A lower value makes the element more transparent.

Example 2 – Image Transparency – Mouseover Effect

Mouse over the images:

The source code looks like this:

We see that the first line of the source code is similar to the source code in Example 1. In addition, we have added an onmouseover attribute and an onmouseout attribute. The onmouseover attribute defines what will happen when the mouse pointer moves over the image. In this case we want the image to NOT be transparent when we move the mouse pointer over it.

The syntax for this in Firefox is: this.style.opacity=1 and the syntax in IE is: this.filters.alpha.opacity=100.

When the mouse pointer moves away from the image, we want the image to be transparent again. This is done in the onmouseout attribute.

Example 3 – Text in Transparent Box

The source code looks like this:

First, we create a div element (class="background") with a fixed height and width, a background image, and a border. Then we create a smaller div (class="transbox") inside the first div element. This div also have a fixed width, a background image, and a border. In addition we make this div transparent.

Inside the transparent div, we add some text inside a p element.

Add a description of the image here

Add a description of the image here

Add a description of the image here

Add a description of the image here

Image Gallery

The following image gallery is created with CSS:

Demo: Navigation Bar

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Navigation Bars

Having easy-to-use navigation is important for any web site.

With CSS you can transform boring HTML menus into good-looking navigation bars.

Navigation Bar = List of Links

A navigation bar needs standard HTML as a base.

In our examples we will build the navigation bar from a standard HTML list.

A navigation bar is basically a list of links, so using the <ul> and <li> elements makes perfect sense:

Now let’s remove the bullets and the margins and padding from the list:

Example explained:

• list-style-type:none – Removes the bullets. A navigation bar does not need list markers
• Setting margins and padding to 0 to remove browser default settings

The code in the example above is the standard code used in both vertical, and horizontal navigation bars.

Vertical Navigation Bar

To build a vertical navigation bar we only need to style the <a> elements, in addition to the code above:

Example explained:

• display:block – Displaying the links as block elements makes the whole link area clickable (not just the text), and it allows us to specify the width
• width:60px – Block elements take up the full width available by default. We want to specify a 60 px width

Note: Always specify the width for <a> elements in a vertical navigation bar. If you omit the width, IE6 can produce unexpected results.

Horizontal Navigation Bar

There are two ways to create a horizontal navigation bar. Using inline or floating list items.

Both methods work fine, but if you want the links to be the same size, you have to use the floating method.

Inline List Items

One way to build a horizontal navigation bar is to specify the <li> elements as inline, in addition to the "standard" code above:

Example explained:

• display:inline; – By default, <li> elements are block elements. Here, we remove the line breaks before and after each list item, to display them on one line

Floating List Items

In the example above the links have different widths.

For all the links to have an equal width, float the <li> elements and specify a width for the <a> elements:

Example explained:

• float:left – use float to get block elements to slide next to each other
• display:block – Displaying the links as block elements makes the whole link area clickable (not just the text), and it allows us to specify the width
• width:60px – Since block elements take up the full width available, they cannot float next to each other. We specify the width of the links to 60px

Syntax

The syntax of pseudo-elements:

CSS classes can also be used with pseudo-elements:

The :first-line Pseudo-element

The "first-line" pseudo-element is used to add a special style to the first line of a text.

In the following example the browser formats the first line of text in a p element according to the style in the "first-line" pseudo-element (where the browser breaks the line, depends on the size of the browser window):

Note: The "first-line" pseudo-element can only be used with block-level elements.

Note: The following properties apply to the "first-line" pseudo-element:

• font properties
• color properties 
• background properties
• word-spacing
• letter-spacing
• text-decoration
• vertical-align
• text-transform
• line-height
• clear

The :first-letter Pseudo-element

The "first-letter" pseudo-element is used to add a special style to the first letter of a text:

Note: The "first-letter" pseudo-element can only be used with block-level elements.

Note: The following properties apply to the "first-letter" pseudo- element: 

• font properties
• color properties 
• background properties
• margin properties
• padding properties
• border properties
• text-decoration
• vertical-align (only if "float" is "none")
• text-transform
• line-height
• float
• clear

Pseudo-elements and CSS Classes

Pseudo-elements can be combined with CSS classes: 

The example above will display the first letter of all paragraphs with class="article", in red.

Multiple Pseudo-elements

Several pseudo-elements can also be combined.

In the following example, the first letter of a paragraph will be red, in an xx-large font size. The rest of the first line will be blue, and in small-caps. The rest of the paragraph will be the default font size and color:

CSS – The :before Pseudo-element

The ":before" pseudo-element can be used to insert some content before the content of an element.

The following example inserts an image before each <h1> element:

CSS – The :after Pseudo-element

The ":after" pseudo-element can be used to insert some content after the content of an element.

The following example inserts an image after each <h1> element:

Pseudo-elements

The "CSS" column indicates in which CSS version the property is defined (CSS1 or CSS2).

Syntax

The syntax of pseudo-classes:

CSS classes can also be used with pseudo-classes:

Anchor Pseudo-classes

Links can be displayed in different ways in a CSS-supporting browser:

Note: a:hover MUST come after a:link and a:visited in the CSS definition in order to be effective!!

Note: a:active MUST come after a:hover in the CSS definition in order to be effective!!

Note: Pseudo-class names are not case-sensitive.

Pseudo-classes and CSS Classes

Pseudo-classes can be combined with CSS classes:

If the link in the example above has been visited, it will be displayed in red.

CSS – The :first-child Pseudo-class

The :first-child pseudo-class matches a specified element that is the first child of another element.

Note: For :first-child to work in IE a <!DOCTYPE> must be declared.

Match the first <p> element

In the following example, the selector matches any <p> element that is the first child of any element:

Match the first <i> element in all <p> elements

In the following example, the selector matches the first <i> element in all <p> elements:

Match all <i> elements in all first child <p> elements

In the following example, the selector matches all <i> elements in <p> elements that are the first child of another element:

CSS – The :lang Pseudo-class

The :lang pseudo-class allows you to define special rules for different languages.

Note: Internet Explorer 8 (and higher) supports the :lang pseudo-class if a <!DOCTYPE> is specified.

In the example below, the :lang class defines the quotation marks for q elements with lang="no":

Pseudo-classes

The "CSS" column indicates in which CSS version the property is defined (CSS1 or CSS2).