border-block-style

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.

The border-block-style CSS property defines the style of the logical block borders of an element, which maps to a physical border style depending on the element's writing mode, directionality, and text orientation. It corresponds to the border-top-style and border-bottom-style, or border-left-style and border-right-style properties depending on the values defined for writing-mode, direction, and text-orientation.

Try it

border-block-style: dotted;
writing-mode: horizontal-tb;

border-block-style: dotted;
writing-mode: vertical-rl;

border-block-style: groove;
writing-mode: horizontal-tb;
direction: rtl;

<section class="default-example" id="default-example">
  <div class="transition-all" id="example-element">
    This is a box with a border around it.
  </div>
</section>

#example-element {
  background-color: #eee;
  color: #000;
  border: 0.75em solid;
  padding: 0.75em;
  width: 80%;
  height: 100px;
  unicode-bidi: bidi-override;
}

The border style in the other dimension can be set with border-inline-style, which sets border-inline-start-style, and border-inline-end-style.

Syntax

/* <'border-style'> values */
border-block-style: dashed;
border-block-style: dotted;
border-block-style: groove;

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

Values

<'border-style'>: The line style of the border. See border-style.

Formal definition

Initial value	`none`
Applies to	all elements
Inherited	no
Computed value	as specified
Animation type	discrete

Formal syntax

border-block-style = 
  <'border-top-style'>{1,2}  

<border-top-style> = 
  <line-style>  

<line-style> = 
  none    |
  hidden  |
  dotted  |
  dashed  |
  solid   |
  double  |
  groove  |
  ridge   |
  inset   |
  outset

Examples

Dashed 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: 5px solid blue;
  border-block-style: dashed;
}

Results

Specifications

Specification
CSS Logical Properties and Values Level 1 # propdef-border-block-style

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android
`border-block-style`	87	87	66	73	14.1	87	66	62	14.5	14.0	87