CSS3 User Interface

CSS3 User Interface

In CSS3, some of the new user interface features are resizing elements, box sizing, and outlining.

In this chapter you will learn about the following user interface properties:

• resize
• box-sizing
• outline-offset

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Browser Support

Property	Browser Support
resize
box-sizing		-moz-	-webkit-	-webkit-
outline-offset

The resize property is only supported in Chrome and Safari.

The box-sizing is supported in Internet Explorer and Opera. Firefox requires the prefix -moz-. Chrome and Safari require the prefix -webkit-.

The outline property is supported in all major browsers, except Internet Explorer.

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CSS3 Resizing

In CSS3, the resize property specifies whether or not an element should be resizable by the user.

This div element is resizable by the user (in Google Chrome and Safari).

The CSS code is as follows:

Example Specify that a div element should be resizable by the user: div { resize:both; overflow:auto; } Try it yourself »

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CSS3 Box Sizing

The box-sizing property allows you to define certain elements to fit an area in a certain way:

Example Specify two bordered boxes side by side: div { box-sizing:border-box; -moz-box-sizing:border-box; /* Firefox */ -webkit-box-sizing:border-box; /* Safari and Chrome */ width:50%; float:left; } Try it yourself »

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CSS3 Outline Offset

The outline-offset property offsets an outline, and draws it beyond the border edge.

Outlines differ from borders in two ways:

• Outlines do not take up space
• Outlines may be non-rectangular

This div has an outline 15px outside the border edge.

The CSS code is as follows:

Example Specify an outline 15px outside the border edge: div { border:2px solid black; outline:2px solid red; outline-offset:15px; } Try it yourself »

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New User-interface Properties

Property	Description	CSS
appearance	Allows you to make an element look like a standard user interface element	3
box-sizing	Allows you to define certain elements to fit an area in a certain way	3
icon	Provides the author the ability to style an element with an iconic equivalent	3
nav-down	Specifies where to navigate when using the arrow-down navigation key	3
nav-index	Specifies the tabbing order for an element	3
nav-left	Specifies where to navigate when using the arrow-left navigation key	3
nav-right	Specifies where to navigate when using the arrow-right navigation key	3
nav-up	Specifies where to navigate when using the arrow-up navigation key	3
outline-offset	Offsets an outline, and draws it beyond the border edge	3
resize	Specifies whether or not an element is resizable by the user	3