update starter ui components

Author: Alexey Ivanov

src/components/app.css

@@ -0,0 +1,38 @@
+.app {
+  text-align: center;
+}
+
+.app__logo {
+  height: 40vmin;
+  pointer-events: none;
+}
+
+@media (prefers-reduced-motion: no-preference) {
+  .app-logo {
+    animation: App-logo-spin infinite 20s linear;
+  }
+}
+
+.app__header {
+  background-color: #282c34;
+  min-height: 100vh;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  font-size: calc(10px + 2vmin);
+  color: white;
+}
+
+.app__link {
+  color: #61dafb;
+}
+
+@keyframes app__logo-spin {
+  from {
+    transform: rotate(0deg);
+  }
+  to {
+    transform: rotate(360deg);
+  }
+}

src/components/app.tsx

@@ -0,0 +1,24 @@
+import React from 'react';
+import './app.css';
+import logo from '../assets/logo.svg';
+
+export const App = (): JSX.Element => {
+  return (
+    <div className="app">
+      <header className="app__header">
+        <img src={logo} className="app__logo" alt="logo" />
+        <p>
+          Edit <code>src/app.tsx</code> and save to reload.
+        </p>
+        <a
+          className="app__link"
+          href="https://reactjs.org"
+          target="_blank"
+          rel="noopener noreferrer"
+        >
+          Learn React
+        </a>
+      </header>
+    </div>
+  );
+};

src/index.tsx

@@ -1,13 +1,10 @@
-import React from "react";
-import ReactDOM from "react-dom";
-
-const App = () => (
-  <h1>My React and TypeScript App!! {new Date().toLocaleDateString()}</h1>
-);
+import React from 'react';
+import ReactDOM from 'react-dom';
+import { App } from './components/app';
 
 ReactDOM.render(
   <React.StrictMode>
     <App />
   </React.StrictMode>,
-  document.getElementById("root")
+  document.getElementById('root'),
 );