used mdi icons instead of font awesome

packages/web/src/themes/ThemeHelmet.js

@@ -0,0 +1,15 @@
+import React from 'react';
+import { Helmet } from 'react-helmet';
+
+export default function ThemeHelmet() {
+  return (
+    <Helmet>
+      <style>{`
+        .color-red { color: red; }
+        .color-green { color: green; }
+        .color-on-statusbar-green { color: lime; }
+        .color-blue { color: blue; }
+        `}</style>
+    </Helmet>
+  );
+}