Solution

src/scripts/main.js

@@ -1 +1,20 @@
 'use strict';
+
+const gallery = document.querySelector('.gallery');
+const preview = document.querySelector('.gallery__large-img');
+
+if (gallery && preview) {
+  gallery.addEventListener('click', (e) => {
+    const link = e.target.closest('a');
+
+    if (!link) {
+      return;
+    }
+
+    e.preventDefault();
+
+    const bigSrc = link.getAttribute('href');
+
+    preview.setAttribute('src', bigSrc);
+  });
+}