conference_main/static/conference_main/styles/_schedule.sass

@@ -12,6 +12,11 @@ $col-time-width: 8%
   @extend .container-fluid
   background-color: var(--color-bg-primary)
 
+  .btn-toggle
+    &.is-active
+      @extend .btn
+      @extend .btn-primary
+
   +media-xs
     +padding(0, y)