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+# M54 Contract UI Migration
+
+## Stopping point
+
+Contract Choice uses the shared M52/M53 chibi hand-drawn UI language with measured modules and verified screenshots. Gameplay, Save, routing and domain services remain unchanged.
+
+## Ordered steps
+
+1. Extract responsive canvas and `ContractHeader`.
+2. Extract `ContractBoard` and difficulty choice slots.
+3. Extract `ContractPartySummary`, action dock and navigation.
+4. Add the same SubViewport visual matrix for 760×360, 844×390 and 1280×720 in zh_CN/en.
+5. Inspect static, dynamic and final renders; fix earliest failing boundary.
+
+## Frozen scope
+
+No new content, battle rules, economy, Save schema, audio, packaging or device release work.
+
+## Acceptance
+
+- Existing Contract View contract marker passes exactly once.
+- All six locale/viewport combinations render without clipping or overlap.
+- Every visible region has one owner: static master, runtime content or hit area.
+- Focused commit is pushed before the next step.
+