id: BT-003B
title: Event Comparison Drilldown
status: in_progress
priority: P1
effort: M
depends_on:
  - BT-003A
tags:
  - backtesting
  - ui
summary: Explain why one ranked strategy beat another on the event comparison page.
acceptance_criteria:
  - Selecting a ranked strategy shows daily path details.
  - UI exposes margin-call days, payoff realized, hedge cost, and final equity.
  - Worst LTV point and breach dates are highlighted.
  - Browser test verifies drilldown content updates when selecting a ranked result.
progress_notes:
  - The drilldown UI and service models are implemented in `app/pages/event_comparison.py` and `app/services/event_comparison_ui.py`.
  - Focused unit coverage is green and direct local-browser validation against a fresh local uvicorn process succeeded.
  - Closure is waiting on the local Docker validation path because `docker compose up -d --build` currently surfaces an environment-specific empty bind-mount/import failure for `./app -> /app/app`.