diff --git a/shared/config/.lycheeignore b/shared/config/.lycheeignore
index f56358aa4..81501e804 100644
--- a/shared/config/.lycheeignore
+++ b/shared/config/.lycheeignore
@@ -33,3 +33,18 @@
 # Lychee treats anything after # as a fragment to verify, but for these
 # single-page-apps the # is part of the URL semantics. Skip fragment check.
 ^https://star-history\.com/#
+
+# --- Unrendered JS template literals (false positives) ---
+# When Lychee parses a .qmd that contains JavaScript using template literals
+# like `https://github.com/${m.github}`, the template literal is URL-encoded
+# in the AST as `$%7B…%7D` and reported as a broken URL. The literal is
+# substituted at runtime with the actual value, so it is never a real URL.
+# Pattern matches any `${ANY.ANY}` template literal residue.
+^https?://[^/]+/[^?#\s]*\$%7B[A-Za-z_][A-Za-z0-9_]*\.[A-Za-z_][A-Za-z0-9_]*%7D
+
+# --- GitHub avatar URLs (lychee unreliably HEADs them) ---
+# `https://github.com/<user>.png(?size=N)?` returns 200 in browsers but lychee
+# regularly returns 4xx/timeout against them due to GitHub's HEAD throttling
+# for unauthenticated avatar requests. Manually verified: every avatar URL
+# flagged by the link-rot tracker is reachable in a browser.
+^https://github\.com/[A-Za-z0-9][A-Za-z0-9-]*\.png(\?size=\d+)?$
diff --git a/slides/teaching.qmd b/slides/teaching.qmd
index fdf0a510b..e759d931c 100644
--- a/slides/teaching.qmd
+++ b/slides/teaching.qmd
@@ -91,7 +91,7 @@ All diagrams are authored as **SVG files** in each chapter's `images/` directory
 To modify a diagram:
 
 1. Edit the `.svg` file in any vector editor (Inkscape, Illustrator, Figma)
-2. Follow the [SVG style guide](https://github.com/harvard-edge/cs249r_book/blob/main/.claude/rules/svg-style.md) for colors and typography
+2. Follow the SVG style guide (palette, typography, canvas conventions) used by the book figures
 3. Rebuild the deck; the Makefile handles SVG-to-PDF conversion
 
 ### Theme Customization