diff --git a/addons/website_slides/static/src/scss/slides_slide_fullscreen.scss b/addons/website_slides/static/src/scss/slides_slide_fullscreen.scss
index 4f7291aa9e1..5d826e38f0a 100644
--- a/addons/website_slides/static/src/scss/slides_slide_fullscreen.scss
+++ b/addons/website_slides/static/src/scss/slides_slide_fullscreen.scss
@@ -56,7 +56,7 @@
             }
         }
 
-        @include media-breakpoint-up (md) {
+        @include media-breakpoint-up (sm) {
             width: $o-wslides-fs-side-width;
 
             &.o_wslides_fs_sidebar_hidden {
diff --git a/addons/website_slides/views/website_slides_templates_lesson_fullscreen.xml b/addons/website_slides/views/website_slides_templates_lesson_fullscreen.xml
index 01bcbd5dd4e..a3a864bb2f1 100644
--- a/addons/website_slides/views/website_slides_templates_lesson_fullscreen.xml
+++ b/addons/website_slides/views/website_slides_templates_lesson_fullscreen.xml
@@ -88,7 +88,7 @@
                             </t>
                         </ul>
                     </div>
-                    <a href="#" class="o_wslides_fs_toggle_sidebar d-lg-none bg-black-50"/>
+                    <a href="#" class="o_wslides_fs_toggle_sidebar d-md-none bg-black-50"/>
                 </div>
             </div>
         </div>