Plan step 19, containment.md C-10. The action row was right-aligned with 24px above it; the side-sheet specs table puts bottom actions on the left in a 72dp row with 16dp above and 24dp below. A dialog's actions stay trailing-aligned — M3 specifies the two differently. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9