diff --git a/moonbit-tour/build/shiki.ts b/moonbit-tour/build/shiki.ts
index 5fdfa814..df931dbc 100644
--- a/moonbit-tour/build/shiki.ts
+++ b/moonbit-tour/build/shiki.ts
@@ -6,14 +6,17 @@ const moonbitLang = JSON.parse(
 );
 
 const highlighter = await shiki.createHighlighter({
-  themes: ["light-plus"],
+  themes: ["light-plus", "dark-plus"],
   langs: [moonbitLang],
 });
 
 function renderMoonBitCode(code: string): string {
   return highlighter.codeToHtml(code, {
     lang: "moonbit",
-    theme: "light-plus",
+    themes: {
+      light: "light-plus",
+      dark: "dark-plus",
+    },
   });
 }
 
diff --git a/moonbit-tour/index.html b/moonbit-tour/index.html
index df8ca7e0..2dd85265 100644
--- a/moonbit-tour/index.html
+++ b/moonbit-tour/index.html
@@ -86,5 +86,26 @@
         </div>
       </section>
     </main>
+    <script>
+      const sunSvg = `<svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor" class="size-6">
+        <path stroke-linecap="round" stroke-linejoin="round" d="M12 3v2.25m6.364.386-1.591 1.591M21 12h-2.25m-.386 6.364-1.591-1.591M12 18.75V21m-4.773-4.227-1.591 1.591M5.25 12H3m4.227-4.773L5.636 5.636M15.75 12a3.75 3.75 0 1 1-7.5 0 3.75 3.75 0 0 1 7.5 0Z" />
+      </svg>
+      `;
+
+      const moonSvg = `<svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor" class="size-6">
+        <path stroke-linecap="round" stroke-linejoin="round" d="M21.752 15.002A9.72 9.72 0 0 1 18 15.75c-5.385 0-9.75-4.365-9.75-9.75 0-1.33.266-2.597.748-3.752A9.753 9.753 0 0 0 3 11.25C3 16.635 7.365 21 12.75 21a9.753 9.753 0 0 0 9.002-5.998Z" />
+      </svg>
+      `;
+
+      const themeButton = document.querySelector("#theme");
+      const theme = localStorage.getItem("theme") ?? "light";
+      if (theme === "light") {
+        document.querySelector("html").classList.remove("dark");
+        themeButton.innerHTML = moonSvg;
+      } else {
+        document.querySelector("html").classList.add("dark");
+        themeButton.innerHTML = sunSvg;
+      }
+    </script>
   </body>
 </html>
diff --git a/moonbit-tour/src/style.css b/moonbit-tour/src/style.css
index bb544399..9aa31872 100644
--- a/moonbit-tour/src/style.css
+++ b/moonbit-tour/src/style.css
@@ -39,3 +39,13 @@
   margin-left: 1rem;
   color: #dc1894 !important;
 }
+
+html.dark .shiki,
+html.dark .shiki span {
+  color: var(--shiki-dark) !important;
+  background-color: var(--shiki-dark-bg) !important;
+  /* Optional, if you also want font styles */
+  font-style: var(--shiki-dark-font-style) !important;
+  font-weight: var(--shiki-dark-font-weight) !important;
+  text-decoration: var(--shiki-dark-text-decoration) !important;
+}