The border-block-color CSS property defines the color of the logical block borders of an element, which maps to a physical border color depending on the element's writing mode, directionality, and text orientation. It corresponds to the border-top-color and border-bottom-color, or border-right-color and border-left-color property depending on the values defined for writing-mode, direction, and text-orientation.
The border color in the other dimension can be set with border-inline-color which sets border-inline-start-color, and border-inline-end-color.
Syntax
border-block-color: yellow; border-block-color: #f5f6f7; /* Global values */ border-block-color: inherit; border-block-color: initial; border-block-color: revert; border-block-color: revert-layer; border-block-color: unset;
Values
- <color>
- 
    The color of the border. 
Formal definition
| Initial value | see individual properties | 
|---|---|
| Applies to | see individual properties | 
| Inherited | see individual properties | 
| Computed value | see individual properties | 
| Animation type | see individual properties | 
Formal syntax
<'border-top-color'>{1,2}Examples
Border with vertical text
HTML
<div> <p class="exampleText">Example text</p> </div>
CSS
div {
  background-color: yellow;
  width: 120px;
  height: 120px;
}
.exampleText {
  writing-mode: vertical-lr;
  border: 10px solid blue;
  border-block-color: red;
}
See also
- CSS Logical Properties and Values
- This property maps to the physical border properties: border-top-color,border-right-color,border-bottom-color, orborder-left-color.
- writing-mode,- direction,- text-orientation