> **Design decision for review.** This changes how every table of up to six columns is laid out, including existing authored ones, and it sits next to the table alignment work in #287. It was split out of #382 so it can be judged separately.

## Why

A new table from `/Table` is a 3×3 grid at about half the prose width, and short authored tables do the same. The design audit (editor finding 13) asked for new tables to use the full width.

## What changed

- Tables now span the prose measure (CSS only, in `packages/editor/src/styles.css`). The rows sit in an anonymous table box that shrinks to fit its columns, so each column in a table of up to six asks for an equal share of the table's width through a container query (`100cqi / N`, where N comes from `:has()` on the row). - Tables with seven or more columns behave as before: at their 7rem minimum they already fill or overflow the measure. - Long content still widens its own column, and the table scrolls as before. On a phone the 7rem minimum still applies, so nothing changes there. - This applies to every table, not only new ones. Limiting it to empty tables would make a table shrink back as soon as you type in it. The trade-off is that short authored tables lose their content-hugging width and get equal columns.

## Screenshots

Before: an authored table and a new table


After


## Testing

- `bun run ci`: passes, including the design contract - `bun run build`: initial bundle unchanged at 246661 B - Checked in the browser at 1440×900. Both tables are 537px wide with no horizontal overflow; before, they were 337px.

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**Hold — design decision for Maggie.** This changes the layout of every existing short table; please don't merge until Maggie has decided.

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