disabled zoom on mobile devices

src/app/components/main-navigation/main-navigation.component.html

@@ -1,4 +1,5 @@
 <link href="https://fonts.googleapis.com/css?family=Roboto:300,400,500" rel="stylesheet"> <!-- getting the google material fonts -->
+<meta name="viewport" content="width=device-width,height=device-height,user-scalable=no,initial-scale=1.0,maximum-scale=1.0,minimum-scale=1.0"> <!-- diables zoom -->
 <mat-sidenav-container class="mat-typography">
 
   <!-- SIDENAV -->