diff --git a/teaching/index.html b/teaching/index.html
index c58b019..dc87af2 100644
--- a/teaching/index.html
+++ b/teaching/index.html
@@ -12,7 +12,7 @@ <h4>“If you can't explain it simply, you don't understand it well enough”</h
     <div class="container">
         <div class="text-center">
             <h2>Teaching Philosophy</h2>
-            <hr>
+            <hr class="mx-auto">
         </div>
         <div class="col-lg-8 col-lg-offset-2 mx-auto text-justify" style="margin-top: 50px">
             <p>
diff --git a/teaching/index.js b/teaching/index.js
index c93a30f..d4c206c 100644
--- a/teaching/index.js
+++ b/teaching/index.js
@@ -33,8 +33,8 @@ function loadCourses(file, id, title) {
 
         const chevron = item.append("a")
             .attr("class", "btn btn-link")
-            .attr("data-toggle", "collapse")
-            .attr("data-target", d => "#" + d.id)
+            .attr("data-bs-toggle", "collapse")
+            .attr("data-bs-target", d => "#" + d.id)
             .attr("aria-expanded", "false");
 
         chevron.append("span")