Resolve ARIA warning

src/lib/components/Lightbox.svelte

@@ -9,7 +9,7 @@
     class="lightbox"
     aria-hidden="true"
     aria-describedby="lb-caption"
-    closedby="any"
+    inert
 >
     <header>
         <button type="button" class="lb-close" aria-label="Close"

static/assets/js/script.js

@@ -51,6 +51,7 @@ function openLightbox(name, type, caption) {
         </picture>`;
     }
     lbCaption.textContent = caption || '';
+    dialog.removeAttribute('inert');
     dialog.setAttribute('aria-hidden', 'false');
     dialog.showModal();
 }
@@ -65,6 +66,7 @@ function closeLightbox() {
     if (lbContent) lbContent.innerHTML = '';
     if (lbCaption) lbCaption.textContent = '';
     dialog.setAttribute('aria-hidden', 'true');
+    dialog.setAttribute('inert', '');
     dialog.close();
 }