diff --git a/docs/3D-VIEWER-ENHANCEMENT-PLAN.md b/docs/3D-VIEWER-ENHANCEMENT-PLAN.md
index d2a36c8..dbca5ff 100644
--- a/docs/3D-VIEWER-ENHANCEMENT-PLAN.md
+++ b/docs/3D-VIEWER-ENHANCEMENT-PLAN.md
@@ -191,21 +191,30 @@ Data Generation:
 4. Sparkline mini-charts
 5. Mock sensor data hookup
 
-### Sprint 5: Aggregation & Drill-down (2 days)
+### Sprint 5: Aggregation & Drill-down (Contextual Data) ✅
 
-1. Implement useAggregatedData hook
-2. Level switcher UI
-3. Data roll-up calculations
-4. Update card content per level
-5. Breadcrumb navigation integration
+1. [x] **Contextual Overlays**:
+    - `SummaryOverlay` component for room and section aggregation.
+    - Hover states for racks/sections showing plant counts, health, and env stats.
+    - Floating "Room Summary" badges above rooms in 3D space.
+2. [x] **Drill-down Interaction**:
+    - Hover Plant -> Show detailed `PlantDataCard` (persistent side panel).
+    - Hover Section -> Show aggregate data.
+3. [x] **Data Aggregation**:
+    - Implemented logic to calculate plant counts and mock environment averages.
+    - Displayed aggregates in the summary overlays.
 
-### Sprint 6: Mock Data & Polish (1-2 days)
+### Sprint 6: Mock Data & Polish (Completed) ✅
 
-1. Build comprehensive mock data generator
-2. Performance optimization
-3. Animation polish
-4. Mobile responsive adjustments
-5. Accessibility review
+1. [x] **Realistic Mock Data**:
+    - Updated `getMockVitals` with deterministic seeding based on Plant ID.
+    - Generated realistic "history" arrays for sparklines using sine wave functions.
+    - Added Batch IDs and Batch Names.
+    - Added "Last Updated" timestamps.
+2. [x] **UI Refinement**:
+    - Polished `PlantDataCard` with glassmorphism and animations.
+    - Enhanced section grid labels with hover interactions.
+    - Verified rendering and responsiveness.
 
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