Glossary

Logical properties

CSS properties keyed to the writing mode and direction (block-start, inline-end, padding-block) rather than the physical screen (top, right, padding-top). Adapt automatically to right-to-left and vertical scripts.

The full set of logical equivalents reached interop in 2022 across Chromium, WebKit, and Gecko. Authoring against margin-block-start instead of margin-top keeps a stylesheet correct for Arabic, Hebrew, Persian, traditional Mongolian, and Japanese vertical layouts without an extra direction-specific sheet. inset-inline-end replaces both right (in LTR) and left (in RTL) in one declaration.