diff --git a/_site/scripts/script.js b/_site/scripts/script.js
index ea9dd0b..58f2775 100644
--- a/_site/scripts/script.js
+++ b/_site/scripts/script.js
@@ -60,6 +60,7 @@ function updateCode() {
         if (!e.dataset['codesrc']) {
             for (const code of e.querySelectorAll('code')) {
                 addCommentStyle(code);
+                addCopyButton(e);
             }
             continue;
         }
@@ -90,6 +91,7 @@ function updateCode() {
                 code.textContent = text;
                 addCommentStyle(code);
                 e.appendChild(code);
+                addCopyButton(e);
             });
         })(e);
     }
@@ -116,6 +118,23 @@ function addCommentStyle(code) {
     }
 }
 
+function addCopyButton(pre) {
+    pre.style.position = "relative";
+
+    const btn = document.createElement("button");
+    btn.classList.add("copy-btn");
+    btn.textContent = "Copy";
+
+    btn.addEventListener("click", () => {
+        navigator.clipboard.writeText(pre.querySelector("code").textContent.trim()).then(() => {
+            btn.textContent = "Copied";
+            setTimeout(() => btn.textContent = "Copy", 700);
+        });
+    });
+
+    pre.insertBefore(btn, pre.firstChild);
+}
+
 let tocLevel = 4;
 
 function disableTOC() {
diff --git a/_site/styles/style.css b/_site/styles/style.css
index cb7876b..dac6b63 100644
--- a/_site/styles/style.css
+++ b/_site/styles/style.css
@@ -748,6 +748,24 @@ ul.toplinks li img {
     opacity: 0.7;
 }
 
+.copy-btn {
+    position: absolute;
+    top: 8px;
+    right: 8px;
+    border-radius: 8px;
+    padding: 2px 6px;
+    background: rgba(0,0,0,0.8);
+    color: #fff;
+    border: none;
+    cursor: pointer;
+    opacity: 0.7;
+    transition: opacity 0.2s ease, background 0.2s ease;
+}
+
+.copy-btn:hover {
+    opacity: 1;
+}
+
 /* test image */
 
 /*body > nav, main {