bootstrap migrate

htmlexamples/courses.html

@@ -41,7 +41,7 @@
 
   <div class="container">
 
-    <header class="row header">
+    <section class="row header">
       <nav class="mt-4" style="--bs-breadcrumb-divider: '/';" aria-label="breadcrumb">
         <ol class="breadcrumb">
           <li class="breadcrumb-item"><a href="#">Main</a></li>
@@ -49,7 +49,7 @@
           <li class="breadcrumb-item active" aria-current="page">Japanese</li>
         </ol>
       </nav>
-    </header>
+    </section>
 
     <section class="row filters">