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<pre class='metadata'>

Title: CSS Basic User Interface Module Level 4

ED: https://drafts.csswg.org/css-ui-4/

Status Text: This specification will include and extend <cite>CSS Basic User Interface Module Level&nbsp;3.</cite> [[CSS-UI-3]]

TR: https://www.w3.org/TR/css-ui-4/

Previous Version: https://www.w3.org/TR/2021/WD-css-ui-4-20210316/

Previous Version: https://www.w3.org/TR/2020/WD-css-ui-4-20200124/

Previous Version: https://www.w3.org/TR/2020/WD-css-ui-4-20200102/

Previous Version: https://www.w3.org/TR/2017/WD-css-ui-4-20171222/

Previous Version: https://www.w3.org/TR/2015/WD-css-ui-4-20150922/

Shortname: css-ui

Level: 4

Status: WD

Date: 2026-01-20

Prepare for TR: yes

Group: csswg

Work Status: Revising

Editor: Florian Rivoal, On behalf of Bloomberg, https://florian.rivoal.net/, w3cid 43241

Editor: Tab Atkins-Bittner, Google, http://xanthir.com/contact/, w3cid 42199

Abstract: This specification describes user interface related

properties and values to style HTML and XML (including XHTML).

It includes and extends user interface related features

from the properties and values of previous CSS levels.

It uses various properties and values

to style basic user interface elements in a document.

At risk: Applicability of 'user-select' to ''::before'' and ''::after''

Can I Use URL: https://drafts.csswg.org/css-ui-3/

Implementation Report: https://wpt.fyi/results/css/css-ui/

WPT Path Prefix: css/css-ui/

Can I Use URL: http://drafts.csswg.org/css-ui-3/

Can I Use URL: https://drafts.csswg.org/css-ui/

Can I Use URL: http://drafts.csswg.org/css-ui/

Can I Use URL: https://www.w3.org/TR/css-ui-3/

Can I Use URL: http://www.w3.org/TR/css-ui-3/

Can I Use URL: https://www.w3.org/TR/css3-ui/

Can I Use URL: http://www.w3.org/TR/css3-ui/

Can I Use URL: https://drafts.csswg.org/css-ui-4/

Can I Use URL: http://drafts.csswg.org/css-ui-4/

Can I Use URL: https://www.w3.org/TR/css-ui-4/

Can I Use URL: http://www.w3.org/TR/css-ui-4/

Ignore Can I Use URL Failure: https://drafts.csswg.org/css-ui-3/

Ignore Can I Use URL Failure: http://drafts.csswg.org/css-ui-3/

Ignore Can I Use URL Failure: https://drafts.csswg.org/css-ui/

Ignore Can I Use URL Failure: http://drafts.csswg.org/css-ui/

Ignore Can I Use URL Failure: https://www.w3.org/TR/css-ui-3/

Ignore Can I Use URL Failure: http://www.w3.org/TR/css-ui-3/

Ignore Can I Use URL Failure: https://www.w3.org/TR/css3-ui/

Ignore Can I Use URL Failure: http://www.w3.org/TR/css3-ui/

Ignore Can I Use URL Failure: https://drafts.csswg.org/css-ui-4/

Ignore Can I Use URL Failure: http://drafts.csswg.org/css-ui-4/

Ignore Can I Use URL Failure: https://www.w3.org/TR/css-ui-4/

Ignore Can I Use URL Failure: http://www.w3.org/TR/css-ui-4/

Indent: 2

</pre>

<pre class=link-defaults>

spec:css-writing-modes-4; type:dfn; text:start

spec:css-writing-modes-4; type:dfn; text:end

spec:css2; type:property; text:min-width

spec:css2; type:property; text:max-width

spec:css2; type:property; text:min-height

spec:css2; type:property; text:max-height

spec:css2; type:property; text:bottom

spec:css2; type:property; text:top

spec:css2; type:property; text:right

spec:css2; type:property; text:visibility

spec:css2; type:property; text:z-index

spec:css-overflow-3; type:dfn; text:ink overflow area

spec:css-pseudo-4; type:selector; text:::before

spec:css-pseudo-4; type:selector; text:::after

spec:css-pseudo-4; type:selector; text:::first-line

spec:css-pseudo-4; type:selector; text:::first-letter

spec:selectors-4; type:selector; text::checked

spec:css-display-3; type:property; text:display

spec:css-color-4; type:value; text:currentcolor

spec:css-overflow-3; type:property; text:overflow

spec:css-sizing-3; type:property; text:box-sizing

spec:css-overflow-4; type:property; text:text-overflow

spec:selectors-4; type:selector; text::active

spec:selectors-4; type:selector; text::enabled

spec:selectors-4; type:selector; text::disabled

spec:css-color-4; type:property; text:color

spec:selectors-4; type:selector; text::focus

spec:selectors-4; type:selector; text::focus-visible

spec:selectors-4; type:dfn; text:host language

spec:css-backgrounds-4; type:property; text:background-image

spec:css-borders-4;

type:property;

text:border

text:border-radius

text:border-color

text:border-top-color

text:border-right-color

text:border-bottom-color

text:border-left-color

text:box-shadow

text:border-image-source

text:border-image-slice

text:border-image-width

text:border-image-outset

text:border-image-repeat

text:border-top-style

text:border-left-style

text:border-right-style

text:border-bottom-style

text:border-top-width

text:border-left-width

text:border-right-width

text:border-bottom-width

text:border-top-color

text:border-left-color

text:border-right-color

text:border-bottom-color

text:border-start-start-radius

text:border-start-end-radius

text:border-end-start-radius

text:border-end-end-radius

text:border-top-left-radius

text:border-top-right-radius

text:border-bottom-left-radius

text:border-bottom-right-radius

text:border-block-start-width

text:border-block-end-width

text:border-inline-start-width

text:border-inline-end-width

text:border-block-start-style

text:border-block-end-style

text:border-inline-start-style

text:border-inline-end-style

text:border-block-start-color

text:border-block-end-color

text:border-inline-start-color

text:border-inline-end-color

text:border-width

type:type;

text:<line-style>

text:<line-width>

type:value; for:border-style;

text:hidden

text:none

spec:dom; type:dfn; text:element

spec:infra; type:dfn; text:user agent

</pre>

<pre class=anchors>

urlPrefix: https://html.spec.whatwg.org/multipage/; spec:HTML

type:attr-value; text:password; for:input/type; url: input.html#attr-input-type-password-keyword

type:element-attr; text:inert; for:html-global; url: interaction.html#the-inert-attribute

</pre>

<style>

.awesome-table td {padding:5px}

.awesome-table {color:#000;background:#fff;margin: auto;}

.fake-textarea {

background: white;

border: inset;

color: black;

display: inline-block;

font-family: monospace;

padding: 0 2px;

}

.fake-textarea.auto {

height: 2lh;

overflow: auto;

resize: both;

width: 10em;

}

.fake-textarea.normal {

width: 10em;

}

.fake-input-type-password {

display: inline-block;

border: 1px solid black;

background: white;

text: black;

width: 20ch;

padding: 0 2px;

}

</style>

<h2 id="intro">

Introduction</h2>

This module describes CSS properties which enable authors

to style user interface related properties and values.

<a href="https://www.w3.org/TR/REC-CSS1#anchor-pseudo-classes">Section 2.1 of CSS1</a> [[CSS1]]

and <a href="https://www.w3.org/TR/CSS2/ui.html">Chapter 18 of CSS2</a> [[CSS21]]

introduced several user interface related properties and values.

<a href="https://www.w3.org/TR/2000/WD-css3-userint-20000216">User Interface for CSS3 (16 February 2000)</a> introduced several new user interface related features.

[[CSS-UI-3]] was later introduced to incorporate, extend, and supersede these.

This specification continues this work, and in turn replaces [[CSS-UI-3]].

<wpt title="Basic UI tests">

inheritance.html

</wpt>

<h3 id="purpose">

Purpose</h3>

The purpose of this specification is to achieve the following objectives:

<ul>

<li>

Extend the user interface features in [[CSS21]] and [[CSS-UI-3]]

<li>

Provide additional CSS mechanisms to augment or replace other

dynamic presentation related features in HTML.

<li>

Introduce directional navigation properties to assist in the construction of

user interfaces which make use of a directional navigation model.

</ul>

<h2 id="interaction">Module Interactions</h2>

This document defines new features not present in earlier specifications.

In addition, it replaces and supersedes [[!CSS-UI-3]],

which itself replaced and superseded the following:

<ul>

<li>

<a href="https://www.w3.org/TR/CSS21/ui.html#cursor-props">Section 18.1</a>,

<a href="https://www.w3.org/TR/CSS21/ui.html#dynamic-outlines">section 18.4</a>,

and Information on the stacking of outlines defined in

<a href="https://www.w3.org/TR/CSS21/zindex.html">Appendix E</a>

of Cascading Style Sheets, level 2, revision 1 [[CSS21]]

<li>

<a href="https://www.w3.org/TR/2000/WD-css3-userint-20000216">User Interface for CSS3 (16 February 2000)</a> [[CSS-UI-3]]

</ul>

Note:

<span id="box-model"></span>

<span id="box-sizing"></span>

<span id="propdef-box-sizing"></span>

<span id="valdef-box-sizing-content-box"></span>

<span id="valdef-box-sizing-border-box"></span>

<span id="min-inner-width"></span>

<span id="max-inner-width"></span>

<span id="min-inner-height"></span>

<span id="max-inner-height"></span>

<span id="example-d824f1dc"></span>

<span id="box-sizing-example"></span>

The 'box-sizing' property was previously defined in this section of the specification,

but has been moved to [[CSS-SIZING-3#box-sizing]].

Note:

<span id="text-overflow" caniuse=text-overflow></span>

<span id="propdef-text-overflow"></span>

<span id="overflow-clip"></span>

<span id="overflow-ellipsis"></span>

<span id="overflow-string"></span>

<span id="funcdef-text-overflow-fade"></span>

<span id="issue-ebe65138"></span>

<span id="issue-2e22b1d9"></span>

<span id="issue-948cb1ee"></span>

<span id="valdef-text-overflow-fade"></span>

<span id="example-160d0058"></span>

<span id="bidi-ellipsis"></span>

<span id="ellipsing-details"></span>

<span id="ellipsis-interaction"></span>

<span id="example-44082941"></span>

<span id="text-overflow-examples"></span>

<span id="issue-4b5212a2"></span>

<span id="ellipsis-scrolling"></span>

<span id="example-45d2531f"></span>

<span id="example-347bbb66"></span>

The 'text-overflow' property was previously defined in this section of the specification,

but has been moved to [[CSS-OVERFLOW-3#text-overflow]].

<h3 id="values">

Value Definitions</h3>

This specification follows the <a href="https://www.w3.org/TR/CSS2/about.html#property-defs">CSS property definition conventions</a> from [[!CSS21]]

using the <a href="https://www.w3.org/TR/css-values-3/#value-defs">value definition syntax</a> from [[!CSS-VALUES-3]].

Value types not defined in this specification are defined in CSS Values &amp; Units [[!CSS-VALUES-3]].

Combination with other CSS modules may expand the definitions of these value types.

In addition to the property-specific values listed in their definitions,

all properties defined in this specification

also accept the <a>CSS-wide keywords</a> as their property value.

For readability they have not been repeated explicitly.

<h2 id="outline-props" caniuse="outline">

Outline properties</h2>

At times, style sheet authors may want to create outlines around

visual objects such as buttons, active form fields, image maps, etc.,

to make them stand out. Outlines differ from borders in the following

ways:

<ol>

<li>Outlines do not take up space.

<li>Outlines contribute to the [=ink overflow area=] of an element.

<li>Outlines may be non-rectangular.

<li>UAs often render outlines on elements in the '':focus-visible'' state.

</ol>

The outline properties control the style of these dynamic outlines.

The stacking of the rendering of these outlines is explicitly left up to implementations

to provide a better user experience per platform.

This supersedes the stacking of outlines as defined in <a href="https://www.w3.org/TR/CSS21/zindex.html">Appendix E of CSS 2.1</a> [[CSS21]].

<strong class="advisement">

Keyboard users,

in particular people with disabilities

who may not be able to interact with the page in any other fashion,

depend on the outline being visible

on elements in the '':focus-visible'' state,

thus authors must not make the outline invisible on such elements

without making sure an alternative highlighting mechanism is provided.

</strong>

The rendering of applying transforms to outlines is left explicitly undefined.

<wpt>

outline-003.html

outline-004.html

outline-005.html

outline-007.html

outline-008.html

outline-009.html

outline-010.html

outline-011.html

outline-012.html

outline-013.html

outline-014.html

outline-015.html

outline-016.html

outline-019.html

outline-020.html

outline-021.html

outline-022.html

outline-024.html

outline-025.html

outline-026.html

outline-027.html

outline-028.html

outline-negative-offset-composited-scroll.html

outline-style-inherit.html

</wpt>

<h3 id="outline">Outlines Shorthand: the 'outline' property</h3>

<pre class="propdef shorthand">

Name: outline

Value: <<'outline-width'>> || <<'outline-style'>> || <<'outline-color'>>

Applies to: all elements

Inherited: no

Percentages: N/A

</pre>

<wpt>

crashtests/outline-scrollIntoView-crash.html

outline-001.html

outline-002.html

outline-003.html

outline-023.html

outline-dynamic.html

outline-with-padding-001.html

parsing/canonical-order-outline-sub-properties-001.html

parsing/outline-invalid.html

parsing/outline-shorthand.html

parsing/outline-valid.html

translucent-outline.html

</wpt>

The 'outline' property is a shorthand property

and sets all three of 'outline-style',

'outline-width',

and 'outline-color'.

In the ambiguous case where

a lone ''outline-style/auto'' value is specified,

or if ''outline-style/auto'' is specified together with an <<'outline-width'>> value,

but without an explicit <<'outline-style'>> or <<'outline-color'>> value,

both 'outline-style' and 'outline-color' are set to ''outine-style/auto''.

Note: The shorthand purposefully omits the 'outline-offset' property,

which determines the position rather than the appearance of the outline,

so that it can cascade independently,

as well as for backwards compatibility reasons.

The outline created with the outline properties is drawn "over" a box,

i.e., the outline is always on top

and doesn't influence the position or size of the box,

or of any other boxes.

Therefore, displaying or suppressing outlines does not cause reflow.

Outlines may be non-rectangular.

For example, if the element is broken across several lines,

the outline should be an outline or minimum set of outlines

that encloses all the element's boxes.

Each part of the outline should be fully connected

rather than open on some sides

(as borders on inline elements are when lines are broken).

The parts of the outline are not required to be rectangular.

To the extent that the outline follows the <a>border edge</a>,

it should follow the 'border-radius' curve,

as well as the 'corner-shape'.

The position of the outline may be affected by descendant boxes.

The dimensions of the drawn outline contribute to the

[=ink overflow area=] of an element.

User agents should use an algorithm for determining

the outline that encloses a region appropriate

for conveying the concept of focus to the user.

Note: This specification does not define the exact position or shape of the outline, but it is typically drawn immediately outside the border box.

Note: The outline is the same on all sides.

In contrast to borders,

there are no ''outline-top'', ''outline-left'', etc. properties.

This specification does not define how multiple overlapping outlines are drawn

or how outlines are drawn for boxes that are partially obscured behind other elements.

<div class="example">

Here's an example of drawing a thick outline around a BUTTON element:

<pre><code class="lang-css">

button { outline: thick solid }

</code></pre>

</div>

Graphical user interfaces may use outlines around elements

to tell the user which element on the page has the focus.

These outlines are shown in addition to any borders,

and switching outlines on and off should not cause the document to reflow.

The focus is the subject of user interaction in a document

(e.g. for entering text or selecting a button).

<div class="example">

For example, to draw a thick black line around elements in the

'':focus-visible'' state, and a thick red line when it is in the

'':active'' state, the following rules can be used:

<pre><code class="lang-css">

:focus-visible { outline: thick solid black }

:active { outline: thick solid red }

</code></pre>

</div>

Note: Since the outline does not affect formatting

(i.e., no space is left for it in the box model),

it may well overlap other elements on the page.

<h3 id="outline-width">

Outline Thickness: the 'outline-width' property</h3>

<pre class="propdef">

Name: outline-width

Value: <<line-width>>

Initial: medium

Applies to: all elements

Inherited: no

Percentages: N/A

Computed value: absolute length, [=snapped as a border width=]

Animation type: by computed value

</pre>

<wpt>

animation/outline-width-composition.html

animation/outline-width-interpolation.html

outline-with-001-crash.html

parsing/outline-width-computed.html

parsing/outline-width-invalid.html

parsing/outline-width-valid.html

</wpt>

The 'outline-width' property accepts

the same values as 'border-width'

([[css-backgrounds-3#border-width]]),

with the same meaning.

<h3 id="outline-style">

Outline Patterns: the 'outline-style' property</h3>

<pre class="propdef">

Name: outline-style

Value: auto | <<outline-line-style>>

Initial: none

Applies to: all elements

Inherited: no

Percentages: N/A

Computed value: specified keyword

Animation type: by computed value

</pre>

<dfn><<outline-line-style>></dfn> accepts

the same values as <<line-style>>

([[css-backgrounds-3#border-style]])

with the same meaning,

except that

<span class=css>hidden</span> is not a legal outline style.

In addition,

the 'outline-style' property

accepts the value ''outline-style/auto''.

The ''outline-style/auto'' value permits the user agent

to render a custom outline style,

typically a style which is either a user interface default for the platform,

or perhaps a style that is richer

than can be described in detail in CSS,

e.g. a rounded edge outline with semi-translucent outer pixels

that appears to glow.

User agents may enable authors to influence the rendering of

''outline-style/auto'' style outlines

via the 'outline-color' property,

but this specification does not define how the rendering is impacted (if at all).

The 'outline-width' property is ignored when 'outline-style' is ''outline-style/auto''.

User agents may treat ''outline-style/auto'' as

''outline-style/solid''.

<wpt>

outline-017.html

outline-018.html

outline-auto-width-001.html

outline-auto-dynamic-change.html

outline-style-011.html

outline-style-012.html

outline-style-013.html

outline-style-014.html

parsing/outline-style-computed.html

parsing/outline-style-invalid.html

parsing/outline-style-valid.html

</wpt>

<h3 id="outline-color">

Outline Colors: the 'outline-color' property</h3>

<pre class="propdef">

Name: outline-color

Value: auto | <<'border-top-color'>>

Initial: auto

Applies to: all elements

Inherited: no

Percentages: N/A

Computed value: see below

Animation type: by computed value

</pre>

<wpt>

animation/outline-color-interpolation.html

outline-color-001.html

outline-color-002.html

outline-color-003.html

outline-color-004.html

parsing/outline-color-computed.html

parsing/outline-color-invalid.html

parsing/outline-color-valid.html

</wpt>

The 'outline-color' property

accepts all values of <<'border-top-color'>>,

as well as the following keywords:

<dl dfn-type=value dfn-for=outline-color>

<dt><dfn>auto</dfn>

<dd>

When 'outline-style' is ''outline-style/auto'',

''outline-color: auto'' computes to ''outline-style/auto''

and represents the [=accent color=].

Otherwise,

''outline-color: auto'' computes to ''currentColor''.

</dl>

See [[css-color-4#resolving-color-values]]

for the computed value of <<color>> values,

and [[css-images-4#stripes]]

for <<image-1D>> values.

<div id=valdef-outline-color-invert class=note>

Earlier versions of this specification had an additional <code>invert</code> value,

performing a color inversion on the pixels on the screen.

This is no longer supported,

and was removed for lack of implementations

(and of intent to implement)

in modern user agents.

See [[css-ui-3#outline-color]] for details.

</div>

<h3 id="outline-offset">

Offsetting the Outline: the 'outline-offset' property</h3>

By default, the outline is drawn starting just outside the <a>border edge</a>.

However, it is possible to offset the outline and draw it beyond the <a>border edge</a>.

<pre class="propdef">

Name: outline-offset

Value: <<length>>

Initial: 0

Applies to: all elements

Inherited: no

Percentages: N/A

Computed value: absolute length

Animation Type: by computed value

</pre>

<wpt>

animation/outline-offset-composition.html

animation/outline-offset-interpolation.html

neg-outline-offset-border-radius-crash.html

negative-outline-offset.html

outline-offset-001.html

outline-offset-table-001.html

outline-offset.html

parsing/outline-offset-computed.html

parsing/outline-offset-invalid.html

parsing/outline-offset-valid.html

</wpt>

If the computed value of 'outline-offset'

is anything other than 0,

then the outline is outset from the <a>border edge</a> by that amount.

<div class="example">

For example,

to leave 2 pixels of space between a focus outline

and the element that has the focus or is active,

the following rule can be used:

<pre><code class="lang-css">

:focus,:active { outline-offset: 2px }

</code></pre>

</div>

<p id=negative-offset>Negative values must cause the outline

to shrink into the border box.

Both the height and the width of the outside of the shape

drawn by the outline should not become smaller

than twice the computed value of the 'outline-width' property

to make sure that an outline can be rendered

even with large negative values.

User agents should apply this constraint

independently in each dimension.

If the outline is drawn as multiple disconnected shapes,

this constraint applies to each shape separately.

<h2 id="resizing">

<!--maintaining old anchors back from when text-overflow was defined here--><span id="resizing-and-overflow"></span>

Resizing</h2>

CSS2.1 provides a mechanism for controlling the appearance of a scrolling mechanism

(e.g. scrollbars)

on block container elements.

This specification adds a mechanism to that for controlling

user resizability of elements as well as the ability to specify text overflow behavior.

<h3 id="resize" caniuse="css-resize">

Resizing Boxes: the 'resize' property</h3>

The 'resize' property allows the author

to specify whether or not an element is resizable by the user,

and if so, along which axis/axes.

<pre class="propdef">

Name: resize

Value: none | both | horizontal | vertical | block | inline

Initial: none

Applies to: elements that are <a>scroll containers</a>

and optionally replaced elements such as images, videos, and iframes

Inherited: no

Percentages: N/A

Computed value: specified keyword

Animation type: discrete

</pre>

<wpt>

parsing/resize-computed.html

parsing/resize-invalid.html

parsing/resize-valid.html

resize-001.html

resize-002.html

resize-003.html

resize-004.html

resize-005.html

resize-006.html

resize-007.html

resize-008.html

resize-009.html

resize-010.html

resize-011.html

resize-012.html

resize-013.html

resize-014.html

resize-015.html

resize-016.html

resize-017.html

resize-018.html

resize-019.html

resize-020.html

resize-021.html

resize-change-margin.html

resize-child-will-change-transform.html

resize-generated-content.html

resize-interactive.html

</wpt>

<dl>

<dt>none

<dd>

The UA does not present a resizing mechanism on the element,

and the user is given no direct manipulation mechanism to resize the element.

<dt>both

<dd>

The UA presents a bidirectional resizing mechanism

to allow the user to adjust both the height and the width of the element.

<dt>horizontal

<dd>

The UA presents a unidirectional horizontal resizing mechanism

to allow the user to adjust only the width of the element.

<dt>vertical

<dd>

The UA presents a unidirectional vertical resizing mechanism

to allow the user to adjust only the height of the element.

<dt>block

<dd>

The UA presents a unidirectional [=block-axis=] resizing mechanism

to allow the user to adjust only the [=block size=] of the element.

<dt>inline

<dd>

The UA presents a unidirectional [=inline-axis=] resizing mechanism

to allow the user to adjust only the [=inline size=] of the element.

</dl>

Currently it is possible to control the appearance of the scrolling mechanism (if any)

on an element using the 'overflow' property

(e.g. <code class="lang-css">overflow: scroll</code> vs. <code class="lang-css">overflow: hidden</code> etc.).

The purpose of the 'resize' property

is to allow control over the appearance and function of the resizing mechanism

(e.g. a resize box or widget) on the element.

Note: The resizing mechanism is NOT the same as the scrolling mechanism,

nor is it related to any UA mechanism for zooming.

The scrolling mechanism allows the user

to determine which portion of the contents of an element is shown.

The resizing mechanism allows the user

to determine the size of the element.

The 'resize' property applies to elements

that are <a>scroll containers</a>.

UAs may also apply it,

regardless of the value of the 'overflow' property,

to:

<ul>

<li>

Replaced elements representing images or videos,

such as <{img}>, <{video}>, <{picture}>, <{svg}>, <{object}>, or <{canvas}>.

<li>

The <{iframe}> element.

</ul>

The effect of the 'resize' property on generated content is undefined.

Implementations should not apply the 'resize' property to generated content.

Note: The 'resize' property may apply to generated content in the future

if there is implementation of <a href="https://drafts.csswg.org/css-pseudo/#CSSPseudoElement-interface">Interface CSSPseudoElement</a>.

When an element is resized by the user,

the user agent sets

the 'width' and 'height' properties

to px unit length values of the size indicated by the user

in the element’s <a href="https://www.w3.org/TR/css-style-attr/#style-attribute">style attribute</a> DOM,

replacing existing property declaration(s), if any,

without ''!important'', if any.

If an element is resized in only one dimension,

only the corresponding property is set, not both.

The precise direction of resizing

(i.e. altering the top-left of the element or altering the bottom-right)

may depend on a number of CSS layout factors,

including whether the element is absolutely positioned,

whether it is positioned using the 'right'

and 'bottom' properties,

whether the language of the element is right-to-left etc.

The UA should consider the direction of resizing

(as determined by CSS layout),

as well as platform conventions and constraints,

when deciding how to convey the resizing mechanism to the user.

The user agent must allow the user to resize the element

with no other constraints than what is imposed by

'min-width', 'max-width', 'min-height', and 'max-height'.

Note: There may be situations in which user attempts to resize an element

appear to be overridden or ignored, e.g. because of ''!important'' cascading declarations that supersede

that element’s <a href="https://www.w3.org/TR/css-style-attr/#style-attribute">style attribute</a>

'width' and 'height' properties in the DOM.

Changes to the computed value of an element's 'resize' property

do not reset changes to the <a href="https://www.w3.org/TR/css-style-attr/#style-attribute">style attribute</a> made due to

user resizing of that element.

<div class="example">

For example,

to make iframes scrollable <em>and</em> resizable,

the following rule can be used:

<pre><code class="lang-css">

iframe,object[type^="text/"],

object[type$="+xml"],object[type="application/xml"]

{

overflow:auto;

resize:both;

}

</code></pre>

</div>

<h2 id="pointing-keyboard">

Pointing Devices and Keyboards</h2>

<h3 id="pointer-interaction">

Pointer interaction</h3>

<h4 id="cursor" caniuse="css3-cursors">

Styling the Cursor: the 'cursor' property</h4>

<pre class="propdef">

Name: cursor

Value: [<<cursor-image>>,]* <<cursor-predefined>>

Initial: auto

Applies to: all elements

Inherited: yes

Percentages: N/A

Computed value: as specified, except with any relative URLs converted to absolute

Animation type: discrete

</pre>

<wpt>

animation/cursor-no-interpolation.html

cgitor-image-png-016-manual.html

cgrsor-image-png-017-manual.html

cgrsor-image-png-019-manual.html

cgrsor-image-png-023-manual.html

cgrsor-image-png-024-manual.html

cgrsor-image-png-025-manual.html

cgrsor-image-png-027-manual.html

cgrsor-image-png-028-manual.html

cgrsor-image-png-036-manual.html

cgrsor-image-png-040-manual.html

cgrsor-image-png-042-manual.html

cursor-001-manual.html

cursor-002-manual.html

cursor-003-manual.html

cursor-004-manual.html

cursor-005-manual.html

cursor-006-manual.html

cursor-007-manual.html

cursor-008-manual.html

cursor-009-manual.html

cursor-010-manual.html

cursor-011-manual.html

cursor-012-manual.html

cursor-013-manual.html

cursor-014-manual.html

cursor-015-manual.html

cursor-016-manual.html

cursor-017-manual.html

cursor-018-manual.html

cursor-019-manual.html

cursor-020-manual.html

cursor-autg-003-manual.html

cursor-auto-001-manual.html

cursor-auto-002-manual.html

cursor-auto-004-manual.html

cursor-auto-005.html

cursor-auto-006-manual.html

cursor-auto-007.html

cursor-border-area.html

cursor-box-004.html

cursor-box-005.html

cursor-box-006.html

cursor-box-007-manual.html

cursor-calc-hotspot.html

cursor-content-area-manual.html

cursor-gover-003-manual.html

cursor-hover-001-manual.html

cursor-hover-002.html

cursor-image-001.html

cursor-image-002.html

cursor-image-003-manual.html

cursor-image-004-manual.html

cursor-image-005-manual.html

cursor-image-005-nfs-manual.html

cursor-image-006-manual.html

cursor-image-008-manual.html

cursor-image-009-manual.html

cursor-image-010-manual.html

cursor-image-011-manual.html

cursor-image-012-manual.html

cursor-image-013.html

cursor-image-014-manual.html

cursor-image-015-manual.html

cursor-image-016-manual.html

cursor-image-017-manual.html

cursor-image-018-manual.html

cursor-image-png-001-manual.html

cursor-image-png-002-manual.html

cursor-image-png-003-manual.html

cursor-image-png-004.html

cursor-image-png-005-manual.html

cursor-image-png-006-manual.html

cursor-image-png-007-manual.html

cursor-image-png-008-manual.html

cursor-image-png-009-manual.html

cursor-image-png-010-manual.html

cursor-image-png-011-manual.html

cursor-image-png-012-manual.html

cursor-image-png-013-manual.html

cursor-image-png-014-manual.html

cursor-image-png-018.html

cursor-image-png-020-manual.html

cursor-image-png-021-manual.html

cursor-image-png-022.html

cursor-image-png-026-manual.html

cursor-image-png-029-manual.html

cursor-image-png-030-manual.html

cursor-image-png-031.html

cursor-image-png-032.html

cursor-image-png-033.html

cursor-image-png-034-manual.html

cursor-image-png-035-manual.html

cursor-image-png-037-manual.html

cursor-image-png-038-manual.html

cursor-image-png-039-manual.html

cursor-image-png-041-manual.html

cursor-image-png-043-manual.html

cursor-imgge-png-015-manual.html

cursor-imgie-007-manual.html

cursor-outline-area-manual.html

cursor-padding-area-manual.html

cursor-pointer-links-001-manual.html

cursor-pointer-links-002-manual.html

cursor-pointer-links-003-manual.html

cursor-text-001-manual.html

cursor-text-002-manual.html

cursor-x-y-001-manual.html

cursor-x-y-002-manual.html

cursor-x-y-003-manual.html

parsing/cursor-computed.html

parsing/cursor-invalid.html

parsing/cursor-valid.html

select-cursor-001-manual.html

</wpt>

This property specifies the type of cursor to be displayed for the pointing device

when the cursor's hotspot is within the element's <a>border edge</a>.

Note: As per [[css-backgrounds-3#border-radius]], the <a>border edge</a> is affected by 'border-radius'.

In the case of overlapping elements,

which element determines the type of cursor

is based on hit testing:

the element determining the cursor

is the one that would receive a click

initiated from this position.

Note: The specifics of hit testing

are out of scope of this specification.

Hit testing will hopefully be defined

in a future revision of CSS or HTML.