eslint added. lots of refactor

web/src/App.jsx

@@ -0,0 +1,34 @@
+import CssBaseline from '@material-ui/core/CssBaseline'
+import { createMuiTheme, MuiThemeProvider } from '@material-ui/core'
+
+import Appbar from './components/Appbar/index'
+
+const baseTheme = createMuiTheme({
+  overrides: {
+    MuiCssBaseline: {
+      '@global': {
+        html: {
+          WebkitFontSmoothing: 'auto',
+        },
+      },
+    },
+  },
+  palette: {
+    primary: {
+      main: '#3fb57a',
+    },
+    secondary: {
+      main: '#FFA724',
+    },
+    tonalOffset: 0.2,
+  },
+})
+
+export default function App() {
+  return (
+    <MuiThemeProvider theme={baseTheme}>
+      <CssBaseline />
+      <Appbar />
+    </MuiThemeProvider>
+  )
+}