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+# Design: Outcome Selection Pattern (2–N Outcomes)
+
+## Objective
+Create a unified, scalable, and mobile-safe outcome selection UI that provides unambiguous feedback for prediction market participants. It must adapt its layout based on the number of outcomes (N).
+
+## Adaptive Layout Patterns
+
+### 1. Binary Selection (N=2)
+- **Pattern:** Side-by-side large cards (Full width on mobile, split columns on desktop).
+- **Interaction:** Single tap selects the card, highlights it with high-contrast borders and an "Active" indicator.
+- **Confirmation:** Vibrant upon selection.
+
+### 2. Multi-Outcome Selection (3 ≤ N ≤ 6)
+- **Pattern:** Grid cards (2 columns on mobile, 3–4 columns on desktop).
+- **Content:** Includes outcome label, current percentage stake, and odds/multiplier.
+- **Safety:** One tap highlights the outcome; second tap triggers confirmation.
+
+### 3. Dense Multi-Outcome (N > 6)
+- **Pattern:** Vertical list view (full width row items).
+- **Scaling:** Supports long labels via multi-line text alignment.
+
+## Visual Design & States
+
+### State: Idle
+- Subtle glassmorphism background.
+- Semi-transparent border.
+
+### State: Selected
+- High-contrast border (amber/green).
+- Pulse animation.
+- Background becomes 10% more opaque.
+
+### Mobile Optimization
+- **Minimum Tap Target:** 48px height per row/card.
+- **Spacing:** 12px gutter between outcomes.
+- **Grip/Scroll:** List view implements a "Safe Scroll" gutter.
+
+## Performance & Accessibility
+- **Screen Readers:** Uses `role="radiogroup"`.
+- **Keyboard:** Full tab navigation support.
+- **Loading:** Skeleton states with distinct heights.