Apply suggestions from code review

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

website/public/styles/global.css

@@ -1598,7 +1598,7 @@ a:hover {
 
 .learning-hub-sidebar {
   position: sticky;
-  top: 24px;
+  top: calc(var(--header-height) + 24px);
   max-height: calc(100vh - 48px);
   overflow-y: auto;
 }

website/src/content/learning-hub/before-after-customization-examples.md

@@ -16,8 +16,6 @@ relatedArticles:
   - ./defining-custom-instructions.md
 ---
 
-# Before/After Customization Examples
-
 The power of GitHub Copilot customization becomes clear when you see concrete examples of how agents, skills, and instructions transform everyday development workflows. This article presents real-world scenarios showing the dramatic difference between default Copilot behavior and customized experiences that align with your team's standards, tools, and practices.
 
 > Note: The following examples illustrate typical before-and-after scenarios. The actual before and after code may vary depending on the model used and any other context present at generation time.

website/src/content/learning-hub/copilot-configuration-basics.md

@@ -364,11 +364,11 @@ A: Use the `excludedFiles` setting in your IDE configuration or create a workspa
 
 **Q: Can I have different settings per project?**
 
-A: Yes! Use workspace settings (`.vscode/settings.json`) for project-specific preferences that don't need to be shared, or use repository settings (`.github/copilot/`) for team-wide customizations that should be version-controlled.
+A: Yes! Use workspace settings (`.vscode/settings.json`) for project-specific preferences that don't need to be shared, or use repository settings (for example, files in `.github/agents/`, `.github/skills/`, `.github/instructions/`, and `.github/copilot-instructions.md`) for team-wide customizations that should be version-controlled.
 
 **Q: How do team settings override personal settings?**
 
-A: Repository settings in `.github/copilot/` have the highest precedence, followed by workspace settings, then user settings. This means team-defined instructions and agents will apply even if your personal settings differ, ensuring consistency across the team.
+A: Repository-level Copilot configuration (such as `.github/agents/`, `.github/skills/`, `.github/instructions/`, and `.github/copilot-instructions.md`) has the highest precedence, followed by workspace settings, then user settings. This means team-defined instructions and agents will apply even if your personal settings differ, ensuring consistency across the team.
 
 **Q: Where should I put customizations that apply to all my projects?**
 

website/src/content/learning-hub/github-copilot-terminology-glossary.md

@@ -14,8 +14,6 @@ relatedArticles:
   - ./copilot-configuration-basics.md
 ---
 
-# GitHub Copilot Terminology Glossary
-
 New to GitHub Copilot customization? This glossary defines common terms you'll encounter while exploring agents, skills, instructions, and related concepts in the Awesome GitHub Copilot ecosystem.
 
 Use this page as a quick reference when reading articles in the Learning Hub or browsing the repository.

website/src/content/learning-hub/understanding-copilot-context.md

@@ -118,7 +118,7 @@ Using `#` to reference specific files gives Copilot precise context about which
 GitHub Copilot has a maximum token limit for how much context it can process at once. When you have many files open or a long chat history, Copilot prioritizes:
 
 1. **Closest proximity**: Code immediately surrounding your cursor
-2. **Explicitly referenced files**: Files you @-mention in chat for CLI, and #-mention for IDE's (VS Code, Visual Studio, JetBrains, etc.)
+2. **Explicitly referenced files**: Files you @-mention in chat for CLI, and #-mention for IDEs (VS Code, Visual Studio, JetBrains, etc.)
 3. **Recently modified files**: Files you've edited recently
 4. **Direct dependencies**: Files imported by your current file
 

website/src/layouts/ArticleLayout.astro

@@ -14,15 +14,32 @@ interface Props {
 const { title, description, estimatedReadingTime, lastUpdated, tags } = Astro.props;
 const base = import.meta.env.BASE_URL;
 
+const createOrderIndexMap = (order: string[]) => {
+  const map = new Map<string, number>();
+  for (let i = 0; i < order.length; i += 1) {
+    map.set(order[i], i);
+  }
+  return map;
+};
+
 const articles = await getCollection('learning-hub');
 
+const fundamentalsOrderIndex = createOrderIndexMap(fundamentalsOrder);
+const referenceOrderIndex = createOrderIndexMap(referenceOrder);
+
 const fundamentals = articles
-  .filter((a) => fundamentalsOrder.includes(a.id))
+  .filter((a) => fundamentalsOrderIndex.has(a.id))
-  .sort((a, b) => fundamentalsOrder.indexOf(a.id) - fundamentalsOrder.indexOf(b.id));
+  .sort(
+    (a, b) =>
+      (fundamentalsOrderIndex.get(a.id) ?? 0) - (fundamentalsOrderIndex.get(b.id) ?? 0),
+  );
 
 const reference = articles
-  .filter((a) => referenceOrder.includes(a.id))
+  .filter((a) => referenceOrderIndex.has(a.id))
-  .sort((a, b) => referenceOrder.indexOf(a.id) - referenceOrder.indexOf(b.id));
+  .sort(
+    (a, b) =>
+      (referenceOrderIndex.get(a.id) ?? 0) - (referenceOrderIndex.get(b.id) ?? 0),
+  );
 
 const currentSlug = Astro.url.pathname.replace(/\/$/, '').split('/').pop();
 ---

website/src/pages/learning-hub/index.astro

@@ -6,13 +6,23 @@ import { fundamentalsOrder, referenceOrder } from '../../config/learning-hub';
 const base = import.meta.env.BASE_URL;
 const articles = await getCollection('learning-hub');
 
+const fundamentalsOrderIndex = {};
+fundamentalsOrder.forEach((id, index) => {
+  fundamentalsOrderIndex[id] = index;
+});
+
+const referenceOrderIndex = {};
+referenceOrder.forEach((id, index) => {
+  referenceOrderIndex[id] = index;
+});
+
 const fundamentals = articles
   .filter((a) => fundamentalsOrder.includes(a.id))
-  .sort((a, b) => fundamentalsOrder.indexOf(a.id) - fundamentalsOrder.indexOf(b.id));
+  .sort((a, b) => fundamentalsOrderIndex[a.id] - fundamentalsOrderIndex[b.id]);
 
 const reference = articles
   .filter((a) => referenceOrder.includes(a.id))
-  .sort((a, b) => referenceOrder.indexOf(a.id) - referenceOrder.indexOf(b.id));
+  .sort((a, b) => referenceOrderIndex[a.id] - referenceOrderIndex[b.id]);
 ---
 
 <BaseLayout title="Learning Hub" description="Curated articles and walkthroughs to help you unlock everything you can do with GitHub Copilot" activeNav="learning-hub">