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CSS Logical Properties and Values is a module of CSS that introduces logical properties and values that provide the ability to control layout through logical, rather than physical, direction and dimension mappings.

The module also defines logical properties and values for properties previously defined in CSS 2.1. Logical properties are writing direction‐relative equivalents of their corresponding physical properties.

Block vs. inline

Logical properties and values use the abstract terms block and inline to describe the direction in which they flow. The physical meaning of these terms depends on the writing mode.

Block dimension
The dimension perpendicular to the flow of text within a line, i.e., the vertical dimension in horizontal writing modes, and the horizontal dimension in vertical writing modes. For standard English text, it is the vertical dimension.
Inline dimension
The dimension parallel to the flow of text within a line, i.e., the horizontal dimension in horizontal writing modes, and the vertical dimension in vertical writing modes. For standard English text, it is the horizontal dimension.

Reference

Properties

Guides

None.

Specifications

Specification Status
CSS Logical Properties and Values Level 1 Editor's Draft

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome (Blink) Edge (Microsoft EdgeHTML) Firefox (Gecko) Internet Explorer (Trident) Safari (WebKit)
1.0 No support 3.6 (1.9.2) No support 3.1 (525)
(Yes) No support 41.0 (41.0) No support ?
No support No support 41.0 (41.0) No support ?
No support No support No support No support ?
No support No support 41.0 (41.0) No support ?

1 The names of the offset-* properties were changed to inset-*1,2 and extended to include inset, inset-block-*, and inset-inline-* properties.

Feature Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support No support 41.0 (41.0) No support No support No support

Document Tags and Contributors

 Contributors to this page: mfluehr, Patrick_Dark, Sebastianz, teoli
 Last updated by: mfluehr,