border-color

Each side can be set individually using border-top-color, border-right-color, border-bottom-color, and border-left-color; or using the writing mode-aware border-block-start-color, border-block-end-color, border-inline-start-color, and border-inline-end-color.

You can find more information about border colors in Borders in Applying color to HTML elements using CSS.

This property is a shorthand for the following CSS properties:

• border-bottom-color
• border-left-color
• border-right-color
• border-top-color

/* <color> values */
border-color: red;

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

/* top | left and right | bottom */
border-color: red rgb(240,30,50,.7) green;

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

/* Global values */
border-color: inherit;
border-color: initial;
border-color: revert;
border-color: revert-layer;
border-color: unset;

The border-color property may be specified using one, two, three, or four values.

• When one value is specified, it applies the same color to all four sides.
• When two values are specified, the first color applies to the top and bottom, the second to the left and right.
• When three values are specified, the first color applies to the top, the second to the left and right, the third to the bottom.
• When four values are specified, the colors apply to the top, right, bottom, and left in that order (clockwise).

<color>

Defines the color of the border.

border-color = 
  <color>{1,4}  

<color> = 
  <absolute-color-base>  |
  currentcolor           |
  <system-color>         

<absolute-color-base> = 
  <hex-color>                |
  <absolute-color-function>  |
  <named-color>              |
  transparent                

<absolute-color-function> = 
  <rgb()>    |
  <rgba()>   |
  <hsl()>    |
  <hsla()>   |
  <hwb()>    |
  <lab()>    |
  <lch()>    |
  <oklab()>  |
  <oklch()>  |
  <color()>  

<rgb()> = 
  rgb( [ <percentage> | none ]{3} [ / [ <alpha-value> | none ] ]? )  |
  rgb( [ <number> | none ]{3} [ / [ <alpha-value> | none ] ]? )  

<hsl()> = 
  hsl( [ <hue> | none ] [ <percentage> | none ] [ <percentage> | none ] [ / [ <alpha-value> | none ] ]? )  

<hwb()> = 
  hwb( [ <hue> | none ] [ <percentage> | none ] [ <percentage> | none ] [ / [ <alpha-value> | none ] ]? )  

<lab()> = 
  lab( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ / [ <alpha-value> | none ] ]? )  

<lch()> = 
  lch( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <hue> | none ] [ / [ <alpha-value> | none ] ]? )  

<oklab()> = 
  oklab( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ / [ <alpha-value> | none ] ]? )  

<oklch()> = 
  oklch( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <hue> | none ] [ / [ <alpha-value> | none ] ]? )  

<color()> = 
  color( <colorspace-params> [ / [ <alpha-value> | none ] ]? )  

<alpha-value> = 
  <number>      |
  <percentage>  

<hue> = 
  <number>  |
  <angle>   |
  none      

<colorspace-params> = 
  <predefined-rgb-params>  |
  <xyz-params>             

<predefined-rgb-params> = 
  <predefined-rgb> [ <number> | <percentage> | none ]{3}  

<xyz-params> = 
  <xyz-space> [ <number> | none ]{3}  

<predefined-rgb> = 
  srgb          |
  srgb-linear   |
  display-p3    |
  a98-rgb       |
  prophoto-rgb  |
  rec2020       

<xyz-space> = 
  xyz      |
  xyz-d50  |
  xyz-d65  

HTML

<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

#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

• Border-color related CSS properties: border, border-top-color, border-right-color, border-bottom-color, border-left-color,
• Other border-related CSS properties: border-width, border-style
• The <color> data type
• Other color-related properties: color, background-color, outline-color, text-decoration-color, text-emphasis-color, text-shadow, caret-color, and column-rule-color
• Applying color to HTML elements using CSS