Apply suggestions from code review

Co-authored-by: Surma <surma@surma.dev>

src/components/intro/index.tsx

@@ -52,10 +52,7 @@ interface State {
 }
 
 export default class Intro extends Component<Props, State> {
-  state: State = {
-    deferredPrompt: undefined,
-    installSource: undefined,
-  };
+  state: State = {};
   private fileInput?: HTMLInputElement;
   private installButton?: HTMLButtonElement;
 
@@ -137,10 +134,7 @@ export default class Intro extends Component<Props, State> {
     deferredPrompt.prompt();
 
     // Wait for the user to accept or dismiss the install prompt
-    const response = await deferredPrompt.userChoice;
-
-    // Get the outcome and log it
-    const outcome = response.outcome;
+    const {outcome} = await deferredPrompt.userChoice;
     ga('send', 'event', 'pwa-install', installSource, outcome);
 
     // If the prompt was dismissed, clear the installSource.

src/components/intro/style.scss

@@ -181,13 +181,21 @@
   background: #fff;
   border: 1px solid #e8e8e8;
 
-  margin-top: 1em;
-
   align-items: center;
   padding: 14px;
   font-size: 1.3rem;
 
+  position: absolute;
+  top: 1rem;
+  right: 1rem;
   display: none;
+  opacity: 0;
+
+  animation: fade-in .3s linear 1s forwards;
+}
+
+@keyframes fade-in {
+	to {opacity: 1;}
 }
 
 .related-links {