[Fire162]

Description

• Make drawer direct children visible when opening or hiding in scss/_drawer.scss.

Motivation & Context

• When a drawer opens via showModal(), the browser runs dialog focusing steps synchronously at time t = 0.
• Because closed drawers use visibility: hidden and animate visibility alongside transform via transitions, the drawer remains visibility: hidden at time t = 0.
• Descendant elements inherit visibility: hidden at that instant and are treated as non-focusable, causing initial focus to fall back to <body> instead of moving into the drawer.
• Adding &:is([open], .hiding) > * { visibility: visible; } makes drawer children immediately visible without waiting on the drawer's transition interpolation, allowing initial focus to land on the first focusable descendant.
• npm run lint, npm run css-test, and npm run js-test pass locally.

Type of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (non-breaking change)
• Breaking change (fix or feature that would change existing functionality)

Checklist

• I have read the contributing guidelines
• My code follows the code style of the project (using npm run lint)
• My change introduces changes to the documentation
• I have updated the documentation accordingly
• I have added tests to cover my changes
• All new and existing tests passed

Related issues

Fixes #43120