update App.js

 import React from "react";
 import React from "react";
 import GlobalStyles from "../Styles/GlobalStyles";
 import GlobalStyles from "../Styles/GlobalStyles";
-import Header from "./Header";
-import Image from "./Image";
-import Grid from "./Grid";
+import { ThemeProvider } from "styled-components";
+import Theme from "../Styles/Theme";
+import MenuBar from "./MenuList/MenuBar";
+import SubMenuBar from "./SubMenuList/SubMenuBar";
+import MainScreen from "./Main/MainScreen";
 
 
 export default () => {
 export default () => {
   return (
   return (
-    <>
-      <GlobalStyles />
-      <Header />
-      <Image />
-      <Grid />
-    </>
+    <ThemeProvider theme={Theme}>
+      <>
+        <GlobalStyles />
+        <MenuBar />
+        <SubMenuBar />
+        <MainScreen />
+      </>
+    </ThemeProvider>
   );
   );
 };
 };