diff --git a/website/README.md b/website/README.md
index bdca0da2..39972b09 100644
--- a/website/README.md
+++ b/website/README.md
@@ -18,6 +18,7 @@ npm run preview  # preview the production build
 ## Site config
 
 - `astro.config.mjs` — Site URL, base path, `locales` block, sidebar (manually maintained).
+  Workshop categories and workshop groups default to collapsed; Starlight automatically expands the branch containing the current page. Keep this behavior when adding groups so similarly named workshops in different categories are not confused.
 - `src/content.config.ts` — Content collection loader. Its `base` points at `../docs`, so lesson Markdown is sourced from the repo-root content directory. Excludes underscore-prefixed directories so support assets such as `_images/` aren't routed as pages.
 - `src/components/` — Site-shell components (`.astro`). Lesson content does **not** live here.
 - `src/pages/` — Standalone Astro routes outside the content collection. Currently just `shared/0-prereqs.astro`, the full-HTML redirect that forwards the legacy `/shared/0-prereqs/` URL to the home page (prerequisites are now per-harness at `/<harness>/0-prerequisites/`).
diff --git a/website/astro.config.mjs b/website/astro.config.mjs
index f4622ef8..b46bb21f 100644
--- a/website/astro.config.mjs
+++ b/website/astro.config.mjs
@@ -60,6 +60,7 @@ export default defineConfig({
         },
         {
           label: 'First steps',
+          collapsed: true,
           translations: {
             'es-ES': 'Primeros pasos',
             'ja-JP': 'はじめの一歩',
@@ -81,6 +82,7 @@ export default defineConfig({
             },
             {
               label: 'GitHub Copilot app',
+              collapsed: true,
               translations: {
                 'ko-KR': 'GitHub Copilot 앱',
               },
@@ -254,6 +256,7 @@ export default defineConfig({
             },
             {
               label: 'GitHub Copilot CLI',
+              collapsed: true,
               items: [
                 {
                   label: 'Overview',
@@ -391,6 +394,7 @@ export default defineConfig({
             },
             {
               label: 'Visual Studio Code',
+              collapsed: true,
               items: [
                 {
                   label: 'Overview',
@@ -530,6 +534,7 @@ export default defineConfig({
         },
         {
           label: 'Real-world development',
+          collapsed: true,
           translations: {
             'ko-KR': '실제 개발',
           },
@@ -543,6 +548,7 @@ export default defineConfig({
             },
             {
               label: 'GitHub Copilot CLI',
+              collapsed: true,
               translations: {
                 'ko-KR': 'GitHub Copilot CLI',
               },
@@ -692,6 +698,7 @@ export default defineConfig({
             },
             {
               label: 'GitHub Copilot app',
+              collapsed: true,
               translations: {
                 'ko-KR': 'GitHub Copilot 앱',
               },
@@ -836,6 +843,7 @@ export default defineConfig({
             },
             {
               label: 'GitHub Copilot cloud agent',
+              collapsed: true,
               translations: {
                 'ko-KR': 'GitHub Copilot 클라우드 에이전트',
               },
@@ -893,6 +901,7 @@ export default defineConfig({
             },
             {
               label: 'Visual Studio Code',
+              collapsed: true,
               translations: {
                 'ko-KR': 'Visual Studio Code',
               },