f0c93ffa3b
The inherited .chat-panel-fill class lands on ChatPanel's new .chat-full root via attribute inheritance, and its display:flex was overriding the grid layout — stacking messages, sidebar, and input bar vertically inside the reading column instead of placing the sidebar in grid col 4. Layout is ChatPanel's responsibility now; .chat-panel-fill only sizes. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>