diff --git a/src/components/TopicDetail/TopicDetail.tsx b/src/components/TopicDetail/TopicDetail.tsx
index 2cf8b0e42..2bdc29a71 100644
--- a/src/components/TopicDetail/TopicDetail.tsx
+++ b/src/components/TopicDetail/TopicDetail.tsx
@@ -30,6 +30,7 @@ import { GitHubIcon } from '../ReactIcons/GitHubIcon.tsx';
 import { GoogleIcon } from '../ReactIcons/GoogleIcon.tsx';
 import { YouTubeIcon } from '../ReactIcons/YouTubeIcon.tsx';
 import { resourceTitleFromId } from '../../lib/roadmap.ts';
+import { lockBodyScroll } from '../../lib/dom.ts';
 
 type TopicDetailProps = {
   resourceTitle?: string;
@@ -262,6 +263,8 @@ export function TopicDetail(props: TopicDetailProps) {
 
   useEffect(() => {
     if (isActive) topicRef?.current?.focus();
+
+    lockBodyScroll(isActive);
   }, [isActive]);
 
   if (!isActive) {
@@ -525,4 +528,4 @@ export function TopicDetail(props: TopicDetailProps) {
       <div className="fixed inset-0 z-30 bg-gray-900 bg-opacity-50 dark:bg-opacity-80"></div>
     </div>
   );
-}
+}
\ No newline at end of file
diff --git a/src/lib/dom.ts b/src/lib/dom.ts
index a8acab84d..6d9fc1679 100644
--- a/src/lib/dom.ts
+++ b/src/lib/dom.ts
@@ -6,3 +6,14 @@ export function replaceChildren(parentNode: Element, newChild: Element) {
   parentNode.innerHTML = '';
   parentNode.append(newChild);
 }
+
+export function lockBodyScroll(shouldLock: boolean) {
+  const isClient = document && 'body' in document;
+  if (!isClient) return;
+
+  if (shouldLock) {
+    document.body.classList.add('overflow-hidden');
+  } else {
+    document.body.classList.remove('overflow-hidden');
+  }
+}
diff --git a/tailwind.config.cjs b/tailwind.config.cjs
index 1471f04e7..d1301c24c 100644
--- a/tailwind.config.cjs
+++ b/tailwind.config.cjs
@@ -7,6 +7,7 @@ module.exports = {
   future: {
     hoverOnlyWhenSupported: true,
   },
+  safelist: ['overflow-hidden'],
   theme: {
     extend: {
       typography: {