diff --git a/.gitignore b/.gitignore
index 5913b3a..f698916 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,8 @@
 # The Institute vault — what never enters git.
-# Rule: git tracks knowledge + code; heavy binaries live on disk and back up separately.
-# (Git LFS for scientific data — OpenSim meshes, checkpoints — is a later option.)
+# Policy: git tracks KNOWLEDGE + SOURCE; only regenerable/large build artifacts are ignored.
+# Papers (.pdf), OpenSim models (.osim), figures (.png/.jpg), and code all sync.
 
-# --- Python ---
+# ── Python ──
 __pycache__/
 *.py[cod]
 *.egg-info/
@@ -11,12 +11,11 @@ venv/
 .pytest_cache/
 *.so
 
-# --- Scientific / engineering binaries ---
+# ── Generated scientific data & checkpoints (regenerable / huge) ──
 *.vtu
 *.vtp
-*.stl
 *.obj
-*.osim            # large OpenSim models; force-add small canonical ones with `git add -f`
+*.stl
 *.pt
 *.pth
 *.ckpt
@@ -25,19 +24,15 @@ venv/
 *.h5
 *.hdf5
 
-# --- Media / renders (generated) ---
+# ── Renders / video (generated) ──
 *.mp4
 *.gif
 *.mov
-*.png             # generated renders; force-add canonical figures explicitly
-*.jpg
-*.jpeg
-*.tiff
+*.webm
 
-# --- LaTeX / build outputs (commit final manuscripts explicitly) ---
+# ── LaTeX / build artifacts ──
 build/
 dist/
-*.log
 *.aux
 *.out
 *.toc
@@ -46,15 +41,15 @@ dist/
 *.synctex.gz
 *.fdb_latexmk
 *.fls
-*.pdf
+*.log
 
-# --- OS / editor noise ---
+# ── OS / editor noise ──
 .DS_Store
 Thumbs.db
 *.swp
 .obsidian/workspace.json
 .obsidian/workspace-mobile.json
 
-# --- Local secrets ---
+# ── Secrets ──
 .env
 *.local
\ No newline at end of file