block-size
Defines the 'height' of an element in a way that respects the writing mode. If you switch from horizontal to vertical text, 'block-size' automatically switches from height to width so your layout remains consistent.
It is documented as part of the CSS Logical Properties and Values specification.
Syntax
/* Usage Example */
.modern-container {
/* Respects writing-mode: usually height in English */
block-size: 300px;
background: #f1f5f9;
}
/* Syntax */
block-size: width;
/* Global values */
block-size: inherit;
block-size: initial;
block-size: revert;
block-size: revert-layer;
block-size: unset;block-size Browser support
Widely available
Since
2021 95% global usage
This feature is well established and works across many devices and browser versions. It has been available across browsers since 2021.
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