🎨 Palette: Add Copy to Clipboard for code blocks

.jules/palette.md

@@ -0,0 +1,3 @@
+## 2026-04-18 - Contextual Action Visibility
+**Learning:** Using `opacity-0 group-hover:opacity-100` for contextual actions (like copy buttons) creates a clean UI but can hide functionality from keyboard users. Adding `focus:opacity-100` is a mandatory companion to ensure the element becomes visible when tabbed into.
+**Action:** Always pair `group-hover:opacity-100` with `focus:opacity-100` for interactive elements to maintain WCAG accessibility.

os2.html

@@ -84,7 +84,10 @@ <h4 class="text-lime-500 font-black text-xs uppercase mb-2">The Zest UI</h4>
                         </div>
                     </div>
                 </div>
-                <div class="code-window">
+                <div class="code-window group">
+                    <button onclick="copyCode(this)" aria-label="Copy code to clipboard" class="absolute top-4 right-4 opacity-0 group-hover:opacity-100 focus:opacity-100 bg-zinc-900 hover:bg-lime-500 hover:text-black text-lime-500 px-3 py-1 text-[10px] font-black uppercase transition-all border border-zinc-700 z-10">
+                        Copy
+                    </button>
                     <pre class="text-lime-500 text-xs leading-loose">
 ; OS*2 SYSTEM_INIT
 move rdi 10          ; ALLOC_SOVEREIGNTY
@@ -170,6 +173,40 @@ <h4 class="text-[10px] font-black text-slate-400 uppercase mb-6 tracking-widest"
                 status.innerText = "Status: Mirror_Sync_In_Progress";
             }
         }
+
+        function copyCode(btn) {
+            const pre = btn.parentElement.querySelector('pre');
+            const code = pre.innerText.trim();
+
+            const performCopy = () => {
+                if (navigator.clipboard && navigator.clipboard.writeText) {
+                    return navigator.clipboard.writeText(code);
+                } else {
+                    const textArea = document.createElement("textarea");
+                    textArea.value = code;
+                    document.body.appendChild(textArea);
+                    textArea.select();
+                    try {
+                        document.execCommand('copy');
+                    } catch (err) {
+                        console.error('Fallback copy failed', err);
+                    }
+                    document.body.removeChild(textArea);
+                    return Promise.resolve();
+                }
+            };
+
+            performCopy().then(() => {
+                const originalText = btn.innerText;
+                btn.innerText = "COPIED!";
+                btn.classList.add('!bg-lime-500', '!text-black');
+                setTimeout(() => {
+                    btn.innerText = originalText;
+                    btn.classList.remove('!bg-lime-500', '!text-black');
+                }, 2000);
+            });
+        }
+
         window.onload = checkAvailability;
     </script>
 </body>