diff --git a/src/uncloseai-embed-modal.js b/src/uncloseai-embed-modal.js
index d83cd8c..422d2a4 100644
--- a/src/uncloseai-embed-modal.js
+++ b/src/uncloseai-embed-modal.js
@@ -95,31 +95,9 @@ function addCodeBlockCopyButtons(element) {
 
 			// Create copy button
 			const copyBtn = document.createElement("button");
-			copyBtn.className = "code-copy-btn";
+			copyBtn.className = "uncloseai-code-copy-btn";
 			copyBtn.textContent = "📋";
 			copyBtn.title = "Copy code";
-			copyBtn.style.cssText = `
-				position: absolute;
-				top: 8px;
-				right: 8px;
-				background: rgba(0, 0, 0, 0.7);
-				color: white;
-				border: none;
-				border-radius: 4px;
-				padding: 4px 8px;
-				cursor: pointer;
-				font-size: 12px;
-				opacity: 0.8;
-				transition: opacity 0.2s;
-				z-index: 10;
-			`;
-
-			copyBtn.onmouseenter = () => {
-				copyBtn.style.opacity = "1";
-			};
-			copyBtn.onmouseleave = () => {
-				copyBtn.style.opacity = "0.8";
-			};
 
 			copyBtn.onclick = async () => {
 				try {
@@ -224,8 +202,7 @@ async function openUncloseaiEmbeddedModalNew() {
 	`;
 
 	const titleContainer = document.createElement("div");
-	titleContainer.style.cssText =
-		"flex: 1; display: flex; flex-direction: column; gap: 4px;";
+	titleContainer.className = "uncloseai-title-container";
 
 	const title = document.createElement("h2");
 	title.innerHTML =
@@ -250,24 +227,7 @@ async function openUncloseaiEmbeddedModalNew() {
 
 	const closeBtn = document.createElement("button");
 	closeBtn.textContent = "✕";
-	closeBtn.style.cssText = `
-		background: rgba(255,255,255,0.2);
-		border: none;
-		color: white;
-		font-size: 20px;
-		width: 36px;
-		height: 36px;
-		border-radius: 50%;
-		cursor: pointer;
-		display: flex;
-		align-items: center;
-		justify-content: center;
-		transition: background 0.2s;
-	`;
-	closeBtn.onmouseover = () =>
-		(closeBtn.style.background = "rgba(255,255,255,0.3)");
-	closeBtn.onmouseout = () =>
-		(closeBtn.style.background = "rgba(255,255,255,0.2)");
+	closeBtn.className = "uncloseai-btn-close";
 	closeBtn.onclick = () => {
 		modal.close();
 		document.body.removeChild(modal);
@@ -280,7 +240,7 @@ async function openUncloseaiEmbeddedModalNew() {
 	menuBtn.className = "uncloseai-modal-settings-btn";
 
 	const headerRight = document.createElement("div");
-	headerRight.style.cssText = "display: flex; gap: 8px; align-items: center;";
+	headerRight.className = "uncloseai-flex-row";
 	headerRight.appendChild(menuBtn);
 	headerRight.appendChild(closeBtn);
 
diff --git a/src/uncloseai-modal-builtin.css b/src/uncloseai-modal-builtin.css
index 01e245c..a943f16 100644
--- a/src/uncloseai-modal-builtin.css
+++ b/src/uncloseai-modal-builtin.css
@@ -554,6 +554,145 @@ dialog#tts-modal {
   transition: width 0.1s;
 }
 
+/* =================================================================== */
+/* COMMON UTILITY CLASSES */
+/* =================================================================== */
+
+/* Container Classes */
+.uncloseai-flex-container {
+  display: flex;
+  flex-direction: column;
+  gap: 12px;
+}
+
+.uncloseai-flex-row {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
+.uncloseai-grid-actions {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
+  gap: 8px;
+}
+
+.uncloseai-panel {
+  background: #ffffff;
+  border: 1px solid #dee2e6;
+  border-radius: 8px;
+  padding: 16px;
+}
+
+/* Button Classes */
+.uncloseai-btn-primary {
+  padding: 8px 16px;
+  background: #f8f9fa;
+  border: 1px solid #dee2e6;
+  border-radius: 20px;
+  cursor: pointer;
+  font-size: 14px;
+  color: #495057;
+  transition: all 0.2s;
+  white-space: nowrap;
+}
+
+.uncloseai-btn-primary:hover {
+  background: #e9ecef;
+}
+
+.uncloseai-btn-small {
+  padding: 4px 8px;
+  font-size: 12px;
+  border-radius: 4px;
+  cursor: pointer;
+  transition: all 0.2s;
+  border: 1px solid #dee2e6;
+  background: #f8f9fa;
+  color: #495057;
+}
+
+.uncloseai-btn-small:hover {
+  background: #e9ecef;
+}
+
+.uncloseai-btn-close {
+  width: 36px;
+  height: 36px;
+  border-radius: 50%;
+  background: rgba(255,255,255,0.2);
+  border: none;
+  color: white;
+  cursor: pointer;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 18px;
+  transition: background 0.2s;
+}
+
+.uncloseai-btn-close:hover {
+  background: rgba(255,255,255,0.3);
+}
+
+/* Form Element Classes */
+.uncloseai-input {
+  width: 100%;
+  padding: 8px 12px;
+  border: 1px solid #dee2e6;
+  border-radius: 6px;
+  font-size: 14px;
+  background: #ffffff;
+  color: #495057;
+}
+
+.uncloseai-label {
+  display: block;
+  margin-bottom: 8px;
+  font-weight: 600;
+  color: #495057;
+}
+
+.uncloseai-section {
+  margin-bottom: 16px;
+}
+
+.uncloseai-title-container {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+}
+
+/* Code block styles */
+.uncloseai-code-copy-btn {
+  position: absolute;
+  top: 8px;
+  right: 8px;
+  background: rgba(0, 0, 0, 0.7);
+  color: white;
+  border: none;
+  padding: 4px 8px;
+  border-radius: 4px;
+  font-size: 12px;
+  cursor: pointer;
+  opacity: 0.8;
+  transition: opacity 0.2s;
+  z-index: 10;
+}
+
+.uncloseai-code-copy-btn:hover {
+  opacity: 1;
+}
+
+/* Message action buttons */
+.uncloseai-message-actions {
+  margin-top: 8px;
+  display: flex;
+  gap: 8px;
+  opacity: 0.7;
+}
+
 /* =================================================================== */
 /* WIDGET LIBRARY STYLES */
 /* =================================================================== */
diff --git a/src/uncloseai-modal-pico.css b/src/uncloseai-modal-pico.css
index 935be20..948e936 100644
--- a/src/uncloseai-modal-pico.css
+++ b/src/uncloseai-modal-pico.css
@@ -605,6 +605,145 @@ dialog#tts-modal {
   transition: width 0.1s;
 }
 
+/* =================================================================== */
+/* COMMON UTILITY CLASSES - PICOCSS OVERRIDES */
+/* =================================================================== */
+
+/* Container Classes */
+.uncloseai-flex-container {
+  display: flex;
+  flex-direction: column;
+  gap: 12px;
+}
+
+.uncloseai-flex-row {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
+.uncloseai-grid-actions {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
+  gap: 8px;
+}
+
+.uncloseai-panel {
+  background: #ffffff;
+  border: 1px solid #dee2e6;
+  border-radius: 8px;
+  padding: 16px;
+}
+
+/* Button Classes */
+.uncloseai-btn-primary {
+  padding: 8px 16px;
+  background: #f8f9fa;
+  border: 1px solid #dee2e6;
+  border-radius: 20px;
+  cursor: pointer;
+  font-size: 14px;
+  color: #495057;
+  transition: all 0.2s;
+  white-space: nowrap;
+}
+
+.uncloseai-btn-primary:hover {
+  background: #e9ecef;
+}
+
+.uncloseai-btn-small {
+  padding: 4px 8px;
+  font-size: 12px;
+  border-radius: 4px;
+  cursor: pointer;
+  transition: all 0.2s;
+  border: 1px solid #dee2e6;
+  background: #f8f9fa;
+  color: #495057;
+}
+
+.uncloseai-btn-small:hover {
+  background: #e9ecef;
+}
+
+.uncloseai-btn-close {
+  width: 36px;
+  height: 36px;
+  border-radius: 50%;
+  background: rgba(255,255,255,0.2);
+  border: none;
+  color: white;
+  cursor: pointer;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 18px;
+  transition: background 0.2s;
+}
+
+.uncloseai-btn-close:hover {
+  background: rgba(255,255,255,0.3);
+}
+
+/* Form Element Classes */
+.uncloseai-input {
+  width: 100%;
+  padding: 8px 12px;
+  border: 1px solid #dee2e6;
+  border-radius: 6px;
+  font-size: 14px;
+  background: #ffffff;
+  color: #495057;
+}
+
+.uncloseai-label {
+  display: block;
+  margin-bottom: 8px;
+  font-weight: 600;
+  color: #495057;
+}
+
+.uncloseai-section {
+  margin-bottom: 16px;
+}
+
+.uncloseai-title-container {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+}
+
+/* Code block styles */
+.uncloseai-code-copy-btn {
+  position: absolute;
+  top: 8px;
+  right: 8px;
+  background: rgba(0, 0, 0, 0.7);
+  color: white;
+  border: none;
+  padding: 4px 8px;
+  border-radius: 4px;
+  font-size: 12px;
+  cursor: pointer;
+  opacity: 0.8;
+  transition: opacity 0.2s;
+  z-index: 10;
+}
+
+.uncloseai-code-copy-btn:hover {
+  opacity: 1;
+}
+
+/* Message action buttons */
+.uncloseai-message-actions {
+  margin-top: 8px;
+  display: flex;
+  gap: 8px;
+  opacity: 0.7;
+}
+
 /* =================================================================== */
 /* WIDGET LIBRARY STYLES - PICOCSS OVERRIDES */
 /* =================================================================== */