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The border-color CSS property is a shorthand for setting the color of the four sides of an element's border: border-top-color, border-right-color, border-bottom-color, border-left-color

/* border-color: color */ /* the color applies to all sides */ 
border-color: red;

/* border-color: top&bottom right&left */
border-color: red #f015ca;

/* border-color: top right&left bottom */
border-color: red yellow green;

/* border-color: top right bottom left */
border-color: red yellow green blue;

border-color: inherit;

Initial valueas each of the properties of the shorthand:
Applies toall elements. It also applies to ::first-letter.
Inheritedno
Mediavisual
Computed valueas each of the properties of the shorthand:
Animation typeas each of the properties of the shorthand:
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Syntax

Values

color
Is a <color> denoting the color to apply to the edges.
inherit
Is a keyword indicating that all four values are inherited from their parent's element calculated value.

Formal syntax

<color>{1,4}

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

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

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

Examples

Complete border-color usage

HTML Content

<div id="justone">
  <p><code>border-color: red;</code> is equivalent to</p>
  <ul><li><code>border-top-color: red;</code></li>
    <li><code>border-right-color: red;</code></li>
    <li><code>border-bottom-color: red;</code></li>
    <li><code>border-left-color: red;</code></li>
  </ul>
</div>
<div id="horzvert">
  <p><code>border-color: gold red;</code> is equivalent to</p>
  <ul><li><code>border-top-color: gold;</code></li>
    <li><code>border-right-color: red;</code></li>
    <li><code>border-bottom-color: gold;</code></li>
    <li><code>border-left-color: red;</code></li>
  </ul>
</div>
<div id="topvertbott">
  <p><code>border-color: red cyan gold;</code> is equivalent to</p>
  <ul><li><code>border-top-color: red;</code></li>
    <li><code>border-right-color: cyan;</code></li>
    <li><code>border-bottom-color: gold;</code></li>
    <li><code>border-left-color: cyan;</code></li>
  </ul>
</div>
<div id="trbl">
  <p><code>border-color: red cyan black gold;</code> is equivalent to</p>
  <ul><li><code>border-top-color: red;</code></li>
    <li><code>border-right-color: cyan;</code></li>
    <li><code>border-bottom-color: black;</code></li>
    <li><code>border-left-color: gold;</code></li>
  </ul>
</div>

CSS Content

#justone {
  border-color: red;
}

#horzvert {
  border-color: gold red;
}

#topvertbott {
  border-color: red cyan gold;
}

#trbl {
  border-color: red cyan black gold;
}

/* Set width and style for all divs */
div {
  border: solid 0.3em;
  width: auto;
  margin: 0.5em;
  padding: 0.5em;
}

ul {
  margin: 0;
  list-style: none;
}

Result

Specifications

Specification Status Comment
CSS Backgrounds and Borders Module Level 3
The definition of 'border-color' in that specification.
Candidate Recommendation The transparent keyword has been removed as it is now a part of the <color> data type.
CSS Level 2 (Revision 1)
The definition of 'border-color' in that specification.
Recommendation The property is now a shorthand property
CSS Level 1
The definition of 'border-color' in that specification.
Recommendation Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1.0 (Yes) 1.0 (1.7 or earlier) [1] 4.0 3.5 1.0 (85)
Feature Android Edge Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support 4.0 (Yes) 1.0 (1.9.2) [1] 7.0 11 1.0

[1] The following Mozilla extensions set the border sides to multiple colors for Gecko based browsers like Firefox. -moz-border-top-colors, -moz-border-right-colors, -moz-border-bottom-colors, -moz-border-left-colors

See also