Add fallback clipboard copy and wrap content in layout container

frontend/style.css

@@ -1036,6 +1036,15 @@ select {
   pointer-events: none;
 }
 
+/* --- Content Wrapper (tabs + content) --- */
+.content-wrapper {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  min-width: 0;
+  overflow: hidden;
+}
+
 /* --- Content Area --- */
 .content-area {
   flex: 1;
@@ -1049,7 +1058,7 @@ select {
 }
 
 /* Center content when sidebar is hidden */
-.sidebar.hidden ~ .content-area {
+.sidebar.hidden ~ .content-wrapper .content-area {
   margin: 0 auto;
   max-width: 1200px;
 }