feat: replace icon fonts with inline SVGs for code copy button and add "Copied" toast notification

css/style.css

@@ -1648,9 +1648,8 @@ footer.footer-modern a:hover {
 	width: 32px;
 	height: 32px;
 	padding: 0;
-	display: inline-flex;
-	align-items: center;
-	justify-content: center;
+	display: grid;
+	place-items: center;
 	border: 1px solid var(--border-color);
 	border-radius: var(--radius-sm);
 	background: var(--bg-subtle);
@@ -1677,14 +1676,34 @@ footer.footer-modern a:hover {
 	border-color: var(--accent);
 }
 
-.code-copy i {
+.code-copy svg {
+	display: block;
+}
+
+/* "Copied" toast — pops up just left of the button */
+.code-copy-toast {
+	position: absolute;
+	top: 0.5rem;
+	right: calc(0.5rem + 32px + 8px); /* clears the 32px button + gap */
+	height: 32px;
 	display: flex;
 	align-items: center;
-	justify-content: center;
-	width: 100%;
-	height: 100%;
-	font-size: 0.95rem;
-	line-height: 1;
+	padding: 0 0.6rem;
+	border-radius: var(--radius-sm);
+	background: var(--accent);
+	color: var(--accent-contrast);
+	font-size: var(--font-size-xs);
+	font-weight: 600;
+	white-space: nowrap;
+	pointer-events: none;
+	opacity: 0;
+	transform: translateX(6px);
+	transition: opacity 0.15s ease, transform 0.15s ease;
+}
+
+.code-copy-toast.is-visible {
+	opacity: 1;
+	transform: translateX(0);
 }
 
 /* Touch devices have no hover — keep the button discoverable */