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
Browser Support

The numbers in the table specify the first browser version that fully supports the property.

Numbers followed by -webkit- or -moz- specify the first version that worked with a prefix.

Property
IE
Chrome
Firebox
Safari
Opera
resize
Not supported
4.0
5.0
4.0 -moz-
4.0
15.0
box-sizing
Partial from 8.0
10.0
4.0 -webkit-
29.0
2.0 -moz-
5.1
3.1 -webkit-
9.5
outline-offset
Not supported
4.0
5.0
4.0 -moz-
4.0
9.5
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 Chrome, Firefox, Safari and Opera 15+).
The CSS code is as follows:

Example

Specify that a <div> element should be resizable by the user:

div {
    resize: both;
    overflow: auto;
}
CSS3 Box Sizing

The box-sizing property is used to tell the browser what the sizing properties (width and height) should include.

Should they include the border-box or just the content-box which is the default value of the width and height properties.

For example, if you want two bordered boxes side by side, it can be achieved through setting box-sizing to "border-box". This forces the browser to render the box with the specified width and height, and place the border and padding inside the box.

Example

Specify two bordered boxes side by side:

div {
    -moz-box-sizing: border-box; /* Firefox */
    box-sizing: border-box;
    width: 50%;
    float: left;
}
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;
}
CSS3 User-interface Properties

The following table lists all the 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