index.html

<!doctype html>
<html>

<head>
    <meta charset="utf-8">
    <meta http-equiv="refresh" name="viewport" content="width=device-width, minimum-scale=1, initial-scale=1, user-scalable=yes">
    <title>Paper-grid</title>
    <script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-bundle.js"></script>
    <script type="module" src="/node_modules/@polymer/iron-component-page/iron-component-page.js"></script>
    <custom-style id="app">
        <style is="custom-style">
            :host, html {
                --iron-component-page-header-color: #00fe70;
                /**
                 * workaround
                 */
                --paper-pink-600 : #00fe70;
            }
        </style>
    </custom-style>
</head>
<body>
    <iron-component-page></iron-component-page>
</body>
</html>