diff --git a/src/__tests__/CopyLinkButton.test.tsx b/src/__tests__/CopyLinkButton.test.tsx
new file mode 100644
index 0000000..4e310e1
--- /dev/null
+++ b/src/__tests__/CopyLinkButton.test.tsx
@@ -0,0 +1,65 @@
+import React from "react";
+import { render, screen, fireEvent, waitFor } from "@testing-library/react";
+import CopyLinkButton from "@/components/CopyLinkButton";
+
+const URL = "https://stellarsplit.app/i/42";
+
+function mockClipboard() {
+  const writeText = vi.fn().mockResolvedValue(undefined);
+  Object.defineProperty(navigator, "clipboard", {
+    value: { writeText },
+    configurable: true,
+    writable: true,
+  });
+  return writeText;
+}
+
+describe("CopyLinkButton", () => {
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it("starts in the idle state", () => {
+    mockClipboard();
+    render(<CopyLinkButton url={URL} />);
+
+    expect(
+      screen.getByRole("button", { name: /copy verification link/i })
+    ).toBeInTheDocument();
+    expect(screen.getByText("Copy Link")).toBeInTheDocument();
+  });
+
+  it("switches to the success state and announces after a successful copy", async () => {
+    const writeText = mockClipboard();
+    render(<CopyLinkButton url={URL} />);
+
+    fireEvent.click(
+      screen.getByRole("button", { name: /copy verification link/i })
+    );
+
+    await waitFor(() =>
+      expect(screen.getByText("Copied!")).toBeInTheDocument()
+    );
+
+    expect(writeText).toHaveBeenCalledWith(URL);
+
+    // Icon swap: the checkmark replaces the link icon.
+    const button = screen.getByRole("button", { name: /copied/i });
+    expect(button.querySelector("svg")).toBeTruthy();
+
+    // Green success styling for the 2s window.
+    expect(button.className).toContain("bg-green-600");
+
+    // Screen-reader announcement.
+    expect(screen.getByText("Link copied")).toBeInTheDocument();
+  });
+
+  it("exposes a polite live region for the announcement", () => {
+    mockClipboard();
+    const { container } = render(<CopyLinkButton url={URL} />);
+
+    const live = container.querySelector('[aria-live="polite"]');
+    expect(live).not.toBeNull();
+    expect(live).toHaveTextContent("");
+  });
+});
diff --git a/src/components/CopyLinkButton.tsx b/src/components/CopyLinkButton.tsx
index e6c2c68..a7f3c82 100644
--- a/src/components/CopyLinkButton.tsx
+++ b/src/components/CopyLinkButton.tsx
@@ -6,12 +6,54 @@ export default function CopyLinkButton({ url }: { url: string }) {
   const { copy, copied } = useCopyToClipboard();
 
   return (
-    <button
-      onClick={() => copy(url)}
-      className="px-3 py-1.5 rounded-lg bg-gray-700 hover:bg-gray-600 text-white text-sm transition-colors focus:outline-none focus-visible:ring-2 focus-visible:ring-indigo-500"
-      aria-label={copied ? "Copied" : "Copy verification link"}
-    >
-      {copied ? "Copied!" : "Copy Link"}
-    </button>
+    <>
+      <button
+        type="button"
+        onClick={() => copy(url)}
+        className={`inline-flex items-center gap-1.5 px-3 py-1.5 rounded-lg text-white text-sm transition-colors duration-300 focus:outline-none focus-visible:ring-2 focus-visible:ring-indigo-500 ${
+          copied
+            ? "bg-green-600 hover:bg-green-600"
+            : "bg-gray-700 hover:bg-gray-600"
+        }`}
+        aria-label={copied ? "Copied" : "Copy verification link"}
+      >
+        {copied ? (
+          <svg
+            className="w-4 h-4"
+            viewBox="0 0 24 24"
+            fill="none"
+            stroke="currentColor"
+            strokeWidth={2}
+            aria-hidden="true"
+          >
+            <path
+              strokeLinecap="round"
+              strokeLinejoin="round"
+              d="M4.5 12.75l6 6 9-13.5"
+            />
+          </svg>
+        ) : (
+          <svg
+            className="w-4 h-4"
+            viewBox="0 0 24 24"
+            fill="none"
+            stroke="currentColor"
+            strokeWidth={1.5}
+            aria-hidden="true"
+          >
+            <path
+              strokeLinecap="round"
+              strokeLinejoin="round"
+              d="M13.19 8.688a4.5 4.5 0 011.242 7.244l-4.5 4.5a4.5 4.5 0 01-6.364-6.364l1.757-1.757m13.35-.622l1.757-1.757a4.5 4.5 0 00-6.364-6.364l-4.5 4.5a4.5 4.5 0 001.242 7.244"
+            />
+          </svg>
+        )}
+        {copied ? "Copied!" : "Copy Link"}
+      </button>
+
+      <span aria-live="polite" className="sr-only">
+        {copied ? "Link copied" : ""}
+      </span>
+    </>
   );
 }