diff --git a/IMPLEMENTATION_PLAN.md b/IMPLEMENTATION_PLAN.md
index df2c801..ff439ad 100644
--- a/IMPLEMENTATION_PLAN.md
+++ b/IMPLEMENTATION_PLAN.md
@@ -15,7 +15,7 @@
 
 ## Tasks
 
-- [ ] **Task 1: Build the boot screen foundation**
+- [x] **Task 1: Build the boot screen foundation**
 
   Create a single `index.html` file with all HTML, CSS, and JavaScript inline. The page starts as a pure black background (`#000`) filling the full viewport. Load Fira Code from Google Fonts (`https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;700&display=swap`). Create a boot screen container (`#boot-screen`) that is `position: fixed; inset: 0; background: #000; z-index: 1000; display: flex; flex-direction: column; justify-content: center; padding: 40px; font-family: 'Fira Code', monospace; font-size: 14px; overflow: hidden;`.
 
diff --git a/progress.txt b/progress.txt
index 9644772..6b9a783 100644
--- a/progress.txt
+++ b/progress.txt
@@ -15,3 +15,12 @@
 - Floating pill nav: NOT full width. max-width 600px, margin: 12px auto, border-radius 100px.
 
 ## Iteration Log
+
+### Iteration 1 — Task 1: Build the boot screen foundation
+- Created `4-vitals-monitor.html` with full boot screen implementation
+- Boot sequence follows guardrail format exactly: CLINICAL TERMINAL v3.2.1, profile init, SYSTEM/USER/ROLE/LOCATION, modules, [OK] lines, READY
+- Timing: 14 lines × 220ms = ~2860ms boot + 400ms pause + 800ms fade = ~4.06s total (within guardrail)
+- Boot text fades to opacity:0, then boot screen is removed and CV content revealed
+- Temporary: boot screen hides directly after fade (Task 2 will insert ECG phase between fade and reveal)
+- CSS variables, all 3 Google Font families loaded, IIFE strict mode JS
+- Learnings: setTimeout delay argument is evaluated at call-time, not in the closure callback, so using a cumulative var in forEach works correctly for staggered timing