block-size - CSS | MDN (original) (raw)

Try it

block-size: 150px;
writing-mode: horizontal-tb;

block-size: 150px;
writing-mode: vertical-rl;

block-size: auto;
writing-mode: horizontal-tb;

block-size: auto;
writing-mode: vertical-lr;

<section class="default-example" id="default-example">
  <div class="transition-all" id="example-element">
    This is a box where you can change the block-size.
  </div>
</section>

#example-element {
  display: flex;
  flex-direction: column;
  background-color: #5b6dcd;
  justify-content: center;
  color: white;
}

Syntax

/* <length> values */
block-size: 300px;
block-size: 25em;
block-size: anchor-size(height);
block-size: calc(anchor-size(--my-anchor block) * 0.75);

/* <percentage> values */
block-size: 75%;

/* Keyword values */
block-size: max-content;
block-size: min-content;
block-size: fit-content;
block-size: fit-content(20em);
block-size: auto;

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

Values

The block-size property takes the same values as the width and height properties.

Formal definition

Initial value auto
Applies to same as width and height
Inherited no
Percentages block-size of containing block
Computed value same as width and height
Animation type a length, percentage or calc();

Formal syntax

block-size =
<'width'>

=
auto |
<length-percentage [0,∞]> |
min-content |
max-content |
fit-content( <length-percentage [0,∞]> ) |
<calc-size()> |
<anchor-size()> |
stretch |
fit-content |
contain

=
|

<calc-size()> =
calc-size( , )

<anchor-size()> =
anchor-size( || []? , ? )

=
|
<calc-size()> |
any |

=
[ '+' | '-' [] []](/en-US/docs/Web/CSS/Guides/Values%5Fand%5Funits/Value%5Fdefinition%5Fsyntax#brackets "Brackets: enclose several entities, combinators, and multipliers to transform them as a single component")*

=

=
width |
height |
block |
inline |
self-block |
self-inline

=
[ '*' | / [] []](/en-US/docs/Web/CSS/Guides/Values%5Fand%5Funits/Value%5Fdefinition%5Fsyntax#brackets "Brackets: enclose several entities, combinators, and multipliers to transform them as a single component")*

=
|
|
|
|
( )

=
e |
pi |
infinity |
-infinity |
NaN

Examples

Block size with vertical text

HTML

<p class="exampleText">Example text</p>

CSS

.exampleText {
  writing-mode: vertical-rl;
  background-color: yellow;
  block-size: 200px;
}

Result

Specifications

Specification
CSS Logical Properties and Values Level 1 # dimension-properties
CSS Box Sizing Module Level 4 # sizing-values

Browser compatibility

See also