added fab class to envelope icon

src/app/home/home.component.html

@@ -70,7 +70,7 @@
 
     <div class="contact-area">
       <a [href]="contactSafeMail">
-        <fa-icon [icon]="faEnvelope" size="3x"></fa-icon>
+        <fa-icon class="fab" [icon]="faEnvelope" size="3x"></fa-icon>
       </a>
 
       <a href="tel:{{globalFields.hrefContactPhone}}">