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The outline-color CSS property sets the color of an element's outline.

It is often more convenient to use the shorthand property outline when defining the appearance of an outline.

An outline is a line that is drawn around an element, outside the border. Unlike the element's border, the outline is drawn outside the element's frame, and may overlap other content. The border, on the other hand, will actually alter the page's layout to ensure that it fits without overlapping anything else (unless you explicitly set it to overlap).

Syntax

/* <color> values */
outline-color: #f92525;
outline-color: rgb(30,222,121);
outline-color: blue;

/* Keyword value */
outline-color: invert;

/* Global values */
outline-color: inherit;
outline-color: initial;
outline-color: unset;

The outline-color property is specified as any one of the values listed below.

Values

<color>
The color of the outline, specified as a <color>.
invert
To ensure the outline is visible, performs a color inversion of the background. Note that browsers are not required to support this value; if they don't, this keyword is considered invalid.

Formal syntax

<color> | invert

where
<color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>

where
<rgb()> = rgb( <percentage>{3} [ / <alpha-value> ]? ) | rgb( <number>{3} [ / <alpha-value> ]? ) | rgb( <percentage>#{3} , <alpha-value>? ) | rgb( <number>#{3} , <alpha-value>? )
<rgba()> = rgba( <percentage>{3} [ / <alpha-value> ]? ) | rgba( <number>{3} [ / <alpha-value> ]? ) | rgba( <percentage>#{3} , <alpha-value>? ) | rgba( <number>#{3} , <alpha-value>? )
<hsl()> = hsl( <hue> <percentage> <percentage> [ / <alpha-value> ]? ) | hsl( <hue>, <percentage>, <percentage>, <alpha-value>? )
<hsla()> = hsla( <hue> <percentage> <percentage> [ / <alpha-value> ]? ) | hsla( <hue>, <percentage>, <percentage>, <alpha-value>? )

where
<alpha-value> = <number> | <percentage>
<hue> = <number> | <angle>

Example

HTML

<p>My outline is blue, as you can see.</p>

CSS

p {
  outline: 2px solid;      /* Set the outline width and style */
  outline-color: #0000FF;  /* Make the outline blue */
  margin: 5px;
}

Accessibility concerns

Custom focus styles commonly involve making adjustments to the outline property. If the color of the outline is adjusted, it is important to ensure that the contrast ratio between it and the background the outline is placed over is high enough that people experiencing low vision conditions will be able to perceive it.

Color contrast ratio is determined by comparing the luminosity of the text and background color values. In order to meet current Web Content Accessibility Guidelines (WCAG), a ratio of 4.5:1 is required for text content and 3:1 for larger text such as headings. Large text is defined as 18.66px and bold or larger, or 24px or larger.

Specifications

Specification Status Comment
CSS Basic User Interface Module Level 3
The definition of 'outline-color' in that specification.
Recommendation No change.
CSS Transitions
The definition of 'outline-color' in that specification.
Working Draft Defines outline-color as animatable.
CSS Level 2 (Revision 1)
The definition of 'outline-color' in that specification.
Recommendation Initial definition.

Initial valueinvert, for browsers supporting it, currentColor for the other
Applies toall elements
Inheritedno
Mediaas each of the properties of the shorthand:
Computed valueFor the keyword invert, the computed value is invert. For the color value, if the value is translucent, the computed value will be the rgba() corresponding one. If it isn't, it will be the rgb() corresponding one. The transparent keyword maps to rgba(0,0,0,0).
Animation typea color
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 1Edge Full support 12Firefox Full support 1.5
Full support 1.5
No support 1 — 3.6
Prefixed
Prefixed Implemented with the vendor prefix: -moz-
IE Full support 8Opera Full support 7Safari Full support 1.2WebView Android ? Chrome Android ? Edge Mobile Full support YesFirefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android ?
invertChrome No support NoEdge ? Firefox No support ? — 3IE Full support 8Opera No support 7 — 15Safari No support NoWebView Android ? Chrome Android ? Edge Mobile ? Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android No support No

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

See also