diff --git a/labapp/app/markdown/lb.md b/labapp/app/markdown/lb.md
index 41cc38b..f39be2a 100644
--- a/labapp/app/markdown/lb.md
+++ b/labapp/app/markdown/lb.md
@@ -88,7 +88,7 @@ Since this is the first exercise, here are some hints (if you need them).
 </p>
 <div class="row">
   <div class="col">
-    <div class="collapse multi-collapse" id="multiCollapseExample1">
+    <div class="collapse multi-collapse data-bs-parent" id="multiCollapseExample1">
       <div class="">
         <img src="/static/load-balancer1.png" width="800px" height="auto" alt="temp">
         <img src="/static/load-balancer2.png" width="800px" height="auto" alt="temp">
@@ -96,14 +96,14 @@ Since this is the first exercise, here are some hints (if you need them).
     </div>
   </div>
   <div class="col">
-    <div class="collapse multi-collapse" id="multiCollapseExample2">
+    <div class="collapse multi-collapse data-bs-parent" id="multiCollapseExample2">
       <div class="">
         <img src="/static/origin-pool.png" width="800px" height="auto" alt="temp">
       </div>
     </div>
   </div>
   <div class="col">
-    <div class="collapse multi-collapse" id="multiCollapseExample3">
+    <div class="collapse multi-collapse data-bs-parent" id="multiCollapseExample3">
       <div class="">
         <img src="/static/origin-server.png" width="800px" height="auto" alt="temp">
       </div>