diff --git a/public/src/uncloseai-modal-builtin.css b/public/src/uncloseai-modal-builtin.css
index cb445fc..8e7ea9d 100644
--- a/public/src/uncloseai-modal-builtin.css
+++ b/public/src/uncloseai-modal-builtin.css
@@ -1149,6 +1149,14 @@ dialog#uncloseai-embedded-modal[data-theme="dark"] .uncloseai-chat-box {
   max-width: min(72vw, 900px);
 }
 
+/* Remove double border: pre has the border, inner code should be transparent */
+.ai-message pre > code {
+  background: none;
+  border: none;
+  padding: 0;
+  border-radius: 0;
+}
+
 /* Mobile: use viewport units since modal is fullscreen */
 @media (max-width: 768px) {
   .ai-message pre {
diff --git a/public/src/uncloseai-modal-pico.css b/public/src/uncloseai-modal-pico.css
index 8ee2875..870d8ff 100644
--- a/public/src/uncloseai-modal-pico.css
+++ b/public/src/uncloseai-modal-pico.css
@@ -1227,6 +1227,14 @@ dialog#uncloseai-embedded-modal[data-theme="dark"] .uncloseai-chat-box {
   max-width: min(72vw, 900px);
 }
 
+/* Remove double border: pre has the border, inner code should be transparent */
+.ai-message pre > code {
+  background: none;
+  border: none;
+  padding: 0;
+  border-radius: 0;
+}
+
 /* Mobile: use viewport units since modal is fullscreen */
 @media (max-width: 768px) {
   .ai-message pre {