Added show/hide controls with animations and hover zone.

src/app/app.module.ts

@@ -1,11 +1,13 @@
 import { NgModule } from '@angular/core';
 import { FormsModule, ReactiveFormsModule } from '@angular/forms';
 import { BrowserModule } from '@angular/platform-browser';
+import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
 import { AppComponent } from './components/app/app.component';
 import { MatInputModule } from '@angular/material/input';
 import { MatIconModule } from '@angular/material/icon';
 import { ClipboardModule } from '@angular/cdk/clipboard';
 import { MatSnackBarModule} from '@angular/material/snack-bar';
+import { MatButtonToggleModule } from '@angular/material/button-toggle';
 import { TranslatePipe } from './translate-pipe';
 import { PeselComponent } from './components/pesel/pesel.component';
 import { NipComponent } from './components/nip/nip.component';
@@ -28,11 +30,13 @@ import { environment } from '../environments/environment';
   ],
     imports: [
         BrowserModule,
+        BrowserAnimationsModule,
         FormsModule,
         MatInputModule,
         MatIconModule,
         ClipboardModule,
         MatSnackBarModule,
+        MatButtonToggleModule,
         ReactiveFormsModule,
         NgOptimizedImage,
         ServiceWorkerModule.register('ngsw-worker.js', {