feat(theme) add ThemeSwitcher.tsx

app/layout.tsx

@@ -1,22 +1,28 @@
-import type { Metadata } from "next";
-import { Inter } from "next/font/google";
-import "./globals.css";
+import type { Metadata } from 'next';
+import { Inter } from 'next/font/google';
+import './globals.css';
+import React from 'react';
+import { ThemeProvider as NextThemesProvider } from 'next-themes';
 
-const inter = Inter({ subsets: ["latin"] });
+const inter = Inter({ subsets: [ 'latin' ] });
 
 export const metadata: Metadata = {
-  title: "Lumither's site",
-  description: "a small corner on internet",
+    title: 'Lumither\'s site',
+    description: 'a small corner on internet'
 };
 
 export default function RootLayout({
-  children,
+    children
 }: Readonly<{
-  children: React.ReactNode;
+    children: React.ReactNode;
 }>) {
-  return (
-    <html lang="en">
-      <body className={inter.className}>{children}</body>
-    </html>
-  );
+    return (
+        <html lang="en" suppressHydrationWarning>
+        <body className={ inter.className }>
+        <NextThemesProvider attribute="class" defaultTheme="dark">
+            { children }
+        </NextThemesProvider>
+        </body>
+        </html>
+    );
 }