diff --git a/general/clipboard.js b/general/clipboard.js
index c392df7..9324be8 100644
--- a/general/clipboard.js
+++ b/general/clipboard.js
@@ -1,4 +1,8 @@
 /* copy code to clipboard */
 function CopyToClipboard(pre) {
+  pre.style.filter = 'invert(1)';
   navigator.clipboard.writeText(pre.firstElementChild.innerHTML);
+  setTimeout(function() {
+    pre.style.filter = 'invert(0)';
+  }, 100);
 }