# Phase 10.6.4.2.1 — Sidebar Structure & Left Offset Hotfix

## Root cause

The Action Center had two separate desktop rules that did not cover the same viewport range:

- the sidebar width was forced to the compact rail width on every desktop viewport from 981px upward;
- hiding the HMH/navigation labels existed only from 981px through 1900px.

At browser zoom levels or wide CSS viewports above 1900px, the sidebar stayed narrow while its text remained visible. The result was the clipped HMH and navigation text shown in the supplied screenshot.

## Fix

The patch makes the compact Action Center rail deterministic for every desktop viewport:

- fixed 88px rail width with matching min/max width;
- explicit LTR and RTL placement;
- hidden brand and navigation labels on all desktop widths;
- fixed 56px icon cells that cannot spill horizontally;
- forced overflow containment and hidden internal scrollbars;
- main content starts exactly after the rail;
- original mobile off-canvas behavior is preserved.

## Functional safety

No Oracle schema, repository save logic, audit persistence, review transition rules, or JSON fallback logic is changed.