enhanced fullcalendar style & demo

- added forgotten themeSystem option in demo
- enhanced toolbar style on mobile

build/scss/plugins/_fullcalendar.scss

@@ -54,11 +54,32 @@
   border-right: 0;
 }
 
-.fc-toolbar {
+.fc-toolbar,
+.fc-toolbar.fc-header-toolbar {
   margin: 0;
   padding: 1rem;
 }
 
+@include media-breakpoint-down(xs) {
+  .fc-toolbar {
+    flex-direction: column;
+
+    .fc-left {
+      order: 1;
+      margin-bottom: .5rem;
+    }
+
+    .fc-center {
+      order: 0;
+      margin-bottom: .375rem;
+    }
+
+    .fc-right {
+      order: 2;
+    }
+  }
+}
+
 .fc-day-number {
   font-size: 20px;
   font-weight: 300;

dist/css/adminlte.css

@@ -20285,11 +20285,33 @@ html.maximized-card {
   border-right: 0;
 }
 
-.fc-toolbar {
+.fc-toolbar,
+.fc-toolbar.fc-header-toolbar {
   margin: 0;
   padding: 1rem;
 }
 
+@media (max-width: 575.98px) {
+  .fc-toolbar {
+    -ms-flex-direction: column;
+    flex-direction: column;
+  }
+  .fc-toolbar .fc-left {
+    -ms-flex-order: 1;
+    order: 1;
+    margin-bottom: .5rem;
+  }
+  .fc-toolbar .fc-center {
+    -ms-flex-order: 0;
+    order: 0;
+    margin-bottom: .375rem;
+  }
+  .fc-toolbar .fc-right {
+    -ms-flex-order: 2;
+    order: 2;
+  }
+}
+
 .fc-day-number {
   font-size: 20px;
   font-weight: 300;

pages/calendar.html

@@ -902,6 +902,7 @@
         center: 'title',
         right : 'dayGridMonth,timeGridWeek,timeGridDay'
       },
+      'themeSystem': 'bootstrap',
       //Random default events
       events    : [
         {