index.html

<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <meta http-equiv="X-UA-Compatible" content="ie=edge" />

        <link
            rel="stylesheet"
            href="https://cdnjs.cloudflare.com/ajax/libs/materialize/1.0.0/css/materialize.min.css"
        />
        <link
            href="https://fonts.googleapis.com/icon?family=Material+Icons"
            rel="stylesheet"
        />

        <script src="https://cdnjs.cloudflare.com/ajax/libs/materialize/1.0.0/js/materialize.min.js"></script>

        <script type="module" src="src/index.js"></script>
        <link rel="stylesheet" type="text/css" href="src/index.css" />

        <title>React</title>
    </head>
    <body>
        <div id="root"></div>
    </body>
</html>