Redesign error

(cherry picked from commit 346722de)

aleksis/apps/alsijil/templates/alsijil/class_register/week_view.html

@@ -425,9 +425,10 @@
       {% endif %}
     </div>
   {% else %}
-    <div class="card red darken-1">
-      <div class="card-content white-text">
+    <div class="card">
+      <div class="card-content">
         <span class="card-title">
+          <i class="material-icons red-text left">warning</i>
           {% blocktrans %}No lessons available{% endblocktrans %}
         </span>
         <p>