Add prism

* add atom code theme
* change nextjs config to mjs
* add remark and rehype plugins

next.config.mjs

@@ -0,0 +1,23 @@
+import remarkFrontmatter from 'remark-frontmatter';
+import mdx from '@next/mdx';
+import rehypePrism from '@mapbox/rehype-prism';
+
+const withMDX = mdx({
+  extension: /\.mdx?$/,
+  options: {
+    remarkPlugins: [remarkFrontmatter],
+    rehypePlugins: [rehypePrism],
+    // providerImportSource: '@mdx-js/react',
+  },
+});
+
+/** @type {import('next').NextConfig} */
+const nextConfig = {
+  reactStrictMode: true,
+  // experimental: {
+  //    reactMode: 'concurrent',
+  // },
+  pageExtensions: ['ts', 'tsx', 'js', 'jsx', 'md', 'mdx'],
+};
+
+export default withMDX(nextConfig);