diff --git a/app/layout.tsx b/app/layout.tsx
index 6f56dd0..34372f8 100644
--- a/app/layout.tsx
+++ b/app/layout.tsx
@@ -1,5 +1,5 @@
 /* eslint-env node */
-import { Footer, Layout, Navbar } from 'nextra-theme-docs'
+import { Footer, Layout, Navbar, useThemeConfig } from 'nextra-theme-docs'
 import { Banner, Head } from 'nextra/components'
 import { getPageMap } from 'nextra/page-map'
 import 'nextra-theme-docs/style.css'
@@ -31,6 +31,7 @@ export const metadata = {
 }
 
 export default async function RootLayout({ children }) {
+  const { darkMode } = useThemeConfig()
   const navbar = (
     <Navbar
       logo={
@@ -82,7 +83,7 @@ export default async function RootLayout({ children }) {
           sidebar={{ defaultMenuCollapseLevel: 1 }}
           pageMap={pageMap}
           // TODO: fix algolia search
-          search={<AlgoliaSearch />}
+          search={<AlgoliaSearch darkMode={darkMode} />}
         >
           {children}
           {/* SpeedInsights in vercel */}
diff --git a/components/docsearch.tsx b/components/docsearch.tsx
index b02490c..928b275 100644
--- a/components/docsearch.tsx
+++ b/components/docsearch.tsx
@@ -2,17 +2,16 @@
 // sample code from https://docsearch.algolia.com/docs/docsearch
 
 import { DocSearch } from '@docsearch/react';
-import { useThemeConfig } from 'nextra-theme-docs'
 
 import '@docsearch/css';
 
-function AlgoliaSearch() {
+function AlgoliaSearch({ darkMode }: { darkMode: boolean }) {
   return (
     <DocSearch
       appId={process.env.NEXT_SEARCH_ALGOLIA_APP_ID || 'NKGLZZZUBC'}
       indexName={process.env.NEXT_SEARCH_ALGOLIA_INDEX_NAME || 'notenextra_trance_0'}
       apiKey={process.env.NEXT_SEARCH_ALGOLIA_API_KEY || '727b389a61e862e590dfab9ce9df31a2'}
-      theme={useThemeConfig().darkMode ? 'dark' : 'light'}
+      theme={darkMode ? 'dark' : 'light'}
     />
   );
 }
diff --git a/content/Math401/Freiwald_summer/Math401_T4.md b/content/Math401/Freiwald_summer/Math401_T4.md
index 6793d5d..a117778 100644
--- a/content/Math401/Freiwald_summer/Math401_T4.md
+++ b/content/Math401/Freiwald_summer/Math401_T4.md
@@ -171,7 +171,6 @@ $$
 
 This is a contradiction, so Bell's inequality is violated.
 
-QED
 </details>
 
 Other revised experiments (eg. Aspect's experiment, Calcium entangled photon experiment) are also conducted and the inequality is still violated.
diff --git a/next.config.mjs b/next.config.mjs
index 641b162..0ace45b 100644
--- a/next.config.mjs
+++ b/next.config.mjs
@@ -24,6 +24,10 @@ export default bundleAnalyzer(withNextra({
   eslint: {
     ignoreDuringBuilds: true,
   },
+  compiler: {
+    // enable console log in production
+    removeConsole: false,
+  },
   // experimental: {    
   //   webpackMemoryOptimizations: true,
   //   staticGenerationMaxConcurrency: 2,   // try 1–3, default is 8