Web/CSS/border-block-start-color

The border-block-start-color CSS property defines the color of the logical block-start border 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, border-right-color, border-bottom-color, or border-left-color property depending on the values defined for writing-mode, direction, and text-orientation.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

Syntax

border-block-start-color: blue;
border-block-start-color: #4c5d21;

Related properties are border-block-end-color, border-inline-start-color, and border-inline-end-color, which define the other border colors of the element.

Values

<'color'>: See border-color

Formal definition

Initial value	`currentcolor`
Applies to	all elements
Inherited	no
Computed value	computed color
Animation type	a color

Formal syntax

<'border-top-color'>

Examples

Border color 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-start-color: red;
}

Results

Specifications

Specification	Status	Comment
CSS Logical Properties and Values Level 1The definition of 'border-block-start-color' in that specification.	Editor's Draft	Initial definition

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`border-block-start-color`	Chrome Full support 69	Edge Full support 79	Firefox Full support 41 Full support 41 No support 38 — 51 Disabled' Disabled' From version 38 until version 51 (exclusive): this feature is behind the `layout.css.vertical-text.enabled` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	IE No support No	Opera Full support 56	Safari Full support 12.1	WebView Android Full support 69	Chrome Android Full support 69	Firefox Android Full support 41 Full support 41 No support 38 — 51 Disabled' Disabled' From version 38 until version 51 (exclusive): this feature is behind the `layout.css.vertical-text.enabled` preference (needs to be set to `true`). To change preferences in Firefox, visit about:config.	Opera Android Full support 48	Safari iOS Full support 12.2	Samsung Internet Android Full support 10.0

Legend

Full support: Full support
No support: No support
User must explicitly enable this feature.': User must explicitly enable this feature.