Grid interactivity: Mover layout and styling issues

[t-hamano]

Description

When the experimental "Grid interactivity" setting is enabled and a grid block is in manual mode, the mover buttons in the block toolbar are not displayed correctly.

Step-by-step reproduction instructions

Enable "Grid interactivity" setting in the Experimental settings page.
Insert a Grid block.
Change "Grid Imte Position" setting to "Manual"
Select a grid item block.

Screenshots, screen recording, code snippet

Top Toolbar disabled

"Show button text labels" is enabled

• Some border colors are incorrect if the "Move left" or "Move right" button is disabled.

Top toolbar enabled

"Show button text labels" is disabled

• The "Move up" and "Move down" buttons are in the wrong position.

"Show button text labels" is enabled

• The "Move up" and "Move down" buttons are in the wrong position.
• Some border colors are incorrect if the "Move left" or "Move right" button is disabled.

Environment info

No response

Please confirm that you have searched existing issues in the repo.

• Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

• Yes