diff --git a/css/archive_tree.css b/css/archive_tree.css
index 70ae630..a21d37c 100644
--- a/css/archive_tree.css
+++ b/css/archive_tree.css
@@ -7,7 +7,7 @@
   padding-bottom: 0;
 }
 .archive-tree-year {
-  font-weight: bold;
+  font-weight: normal;
 }
 .archive-tree-month {
   margin-left: 2em;
diff --git a/src/Plugin/Block/ArchiveTreeBlock.php b/src/Plugin/Block/ArchiveTreeBlock.php
index 601ee02..5ad2ed0 100644
--- a/src/Plugin/Block/ArchiveTreeBlock.php
+++ b/src/Plugin/Block/ArchiveTreeBlock.php
@@ -72,27 +72,35 @@ class ArchiveTreeBlock extends BlockBase {
         '#markup' => $this->t('No content types selected.'),
       ];
     }
+    // 1. Get node IDs with access check.
     $query = $storage->getQuery()
       ->condition('type', $types, 'IN')
       ->condition('status', 1)
       ->sort('created', 'DESC')
       ->accessCheck(TRUE);
     $nids = $query->execute();
-    $nodes = $storage->loadMultiple($nids);
 
     $tree = [];
-    foreach ($nodes as $node) {
-      $created = $node->getCreatedTime();
-      $year = date('Y', $created);
-      $month = date('m', $created);
-      if (!isset($tree[$year])) {
-        $tree[$year] = ['count' => 0, 'months' => []];
+    if (!empty($nids)) {
+      // 2. Fetch only nid and created fields for those nodes.
+      $connection = \Drupal::database();
+      $result = $connection->select('node_field_data', 'n')
+        ->fields('n', ['nid', 'created'])
+        ->condition('n.nid', $nids, 'IN')
+        ->execute();
+      foreach ($result as $row) {
+        $created = $row->created;
+        $year = date('Y', $created);
+        $month = date('m', $created);
+        if (!isset($tree[$year])) {
+          $tree[$year] = ['count' => 0, 'months' => []];
+        }
+        if (!isset($tree[$year]['months'][$month])) {
+          $tree[$year]['months'][$month] = ['count' => 0];
+        }
+        $tree[$year]['count']++;
+        $tree[$year]['months'][$month]['count']++;
       }
-      if (!isset($tree[$year]['months'][$month])) {
-        $tree[$year]['months'][$month] = ['count' => 0];
-      }
-      $tree[$year]['count']++;
-      $tree[$year]['months'][$month]['count']++;
     }
 
     krsort($tree); // Descending years