Improve unfurl layout & resize to 1200x600

frontend/src/app/components/address/address-preview.component.html

@@ -44,7 +44,7 @@
     <div class="w-100 d-block d-md-none"></div>
     <div class="col-md qrcode-col">
       <div class="qr-wrapper">
-        <app-qrcode [data]="address.address" [size]="370"></app-qrcode>
+        <app-qrcode [data]="address.address" [size]="448"></app-qrcode>
       </div>
     </div>
   </div>