Remove useless code

src/app/components/shared/footer/footer.component.html

 <footer>
   <mat-toolbar>
-    <button mat-button (click)="navToBlog()">Blog</button>
+    <button mat-button (click)="navToBlog()">
+      <mat-icon>notes</mat-icon>
+      Blog
+    </button>
     <span class="fill-remaining-space"></span>
-    <button mat-button (click)="navToDSGVO()">DSGVO</button>
+    <button mat-button (click)="navToDSGVO()">
+      <mat-icon>security</mat-icon>
+      DSGVO
+    </button>
     <span class="fill-remaining-space"></span>
-    <button mat-button (click)="navToImprint()">Impressum</button>
+    <button mat-button (click)="navToImprint()">
+      <mat-icon>info</mat-icon>
+      Impressum
+    </button>
   </mat-toolbar>
 </footer>

src/app/components/shared/footer/footer.component.scss

 footer {
-    overflow-y: auto;   
-}
-
-mat-expansion-panel {
-  background-color: rgb(235, 235, 235);
-  color: rgb(60, 60, 60);  
-  height: auto;
+    overflow-y: auto;
 }
 
 mat-toolbar {
   background-color: rgb(240, 240, 240);
-  color: rgb(140, 140, 140);  
+  color: rgb(140, 140, 140);
   height: auto;
 }
 
 button {
   min-height: 28px;
   font-size: 12px;
-  color: rgb(140, 140, 140);  
+  color: rgb(140, 140, 140);
 }
-
-.container {
-  display: flex;
-  justify-content: space-around;
-}
-
-/* Small screens */
-@media all and (max-width: 300px) {
-  .container {
-    flex-direction: column;
-    margin: auto;
-  }
-
-  mat-toolbar {
-    height: auto;
-  }
-}
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