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+# Admin Dashboard Hero Design
+
+## System-health tiles
+Hero section for admin dashboard showing system health at a glance.
+
+## Tiles
+- **API Status**: green/yellow/red with uptime %
+- **Active Users**: count + 24h trend arrow
+- **Queue Depth**: pending tasks with threshold warning
+- **Error Rate**: % with sparkline
+- **DB Health**: connection pool status
+
+## Layout
+- 5-column responsive grid
+- Each tile: icon + metric + trend indicator
+- Skeleton loading state
+- Auto-refresh every 30s with subtle animation
+
+Closes #489
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