diff --git a/.env b/.env
new file mode 100644
index 0000000..ec7c1ec
--- /dev/null
+++ b/.env
@@ -0,0 +1 @@
+VITE_DATE="2024-10-03T05:55:58.579Z"
\ No newline at end of file
diff --git a/index.html b/index.html
index d101bd0..c18b284 100644
--- a/index.html
+++ b/index.html
@@ -1,10 +1,21 @@
 <!DOCTYPE html>
-<html lang="en">
+<html lang="en" prefix="og: https://ogp.me/ns#">
   <head>
     <meta charset="UTF-8" />
     <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>Conway's Game of Life in 3D</title>
+
+    <link rel="canonical" href="https://rei1024.github.io/game-of-life-3d/" />
+
+    <meta name="author" content="Rei" />
+
+    <meta name="date" content="%VITE_DATE%" />
+
+    <meta
+      property="og:image"
+      content="https://rei1024.github.io/game-of-life-3d/ogp.jpg"
+    />
   </head>
   <body>
     <canvas id="renderCanvas"></canvas>
@@ -32,7 +43,7 @@ <h2>Settings</h2>
             <input type="checkbox" id="auto-random" />
           </p>
           <p>
-            <label for="auto-rotate">Auto Rotate:</label>
+            <label for="auto-rotate">Auto rotate:</label>
             <input type="checkbox" id="auto-rotate" />
           </p>
           <p>
diff --git a/package.json b/package.json
index 585bafe..d728882 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,7 @@
   "type": "module",
   "scripts": {
     "dev": "vite",
-    "build": "tsc && vite build",
+    "build": "tsc && node prebuild.js && vite build",
     "preview": "vite preview"
   },
   "devDependencies": {
diff --git a/prebuild.js b/prebuild.js
new file mode 100644
index 0000000..d44d0f4
--- /dev/null
+++ b/prebuild.js
@@ -0,0 +1,7 @@
+import { writeFile } from "node:fs/promises";
+
+async function main() {
+  await writeFile(".env", `VITE_DATE="${new Date().toISOString()}"`);
+}
+
+main();
diff --git a/public/ogp.png b/public/ogp.png
new file mode 100644
index 0000000..f0c6ad8
Binary files /dev/null and b/public/ogp.png differ
