CSSworkingbaseline-2023
Logical properties
Write CSS that flips with the writing mode.
margin-left is hard-coded to physical space. margin-inline-start follows the text — so the same rule does the right thing in English, Arabic, and vertical Japanese without a single override.
Center a card with margin-inline: auto
HTML+CSS+JSintro Press Run to execute
The card sits centred in the dark page band because margin-inline: auto splits the leftover horizontal space into equal start and end margins — but only because max-inline-size: 360px caps the width so there is leftover space to share. It is the flow-relative replacement for margin: 0 auto, and would centre on the correct axis even under writing-mode: vertical-rl.