diff --git a/configure.phtml b/configure.phtml
index 883bd76..47cd57f 100644
--- a/configure.phtml
+++ b/configure.phtml
@@ -54,6 +54,13 @@
       </select>
     </div>
   </div>
+  <div class="form-group">
+    <label class="group-name" for="kagi_custom_css"><?php echo _t('ext.kagiSummarizer.configure.kagi_custom_css'); ?></label>
+    <div class="group-controls">
+      <input type="text" name="kagi_custom_css" id="kagi_custom_css" value="<?php echo $kagi_custom_css; ?>">
+      <p><small><?php echo _t('ext.kagiSummarizer.configure.kagi_custom_css_help'); ?></small></p>
+    </div>
+  </div>
   <div class="form-group form-actions">
     <div class="group-controls">
       <button type="submit" class="btn btn-important"><?php echo _t('gen.action.submit'); ?></button>
diff --git a/extension.php b/extension.php
index 3179e24..f7f98af 100644
--- a/extension.php
+++ b/extension.php
@@ -20,11 +20,13 @@ class KagiSummarizerExtension extends Minz_Extension {
       }
       FreshRSS_Context::$user_conf->kagi_token = $kagi_token;
       FreshRSS_Context::$user_conf->kagi_language = Minz_Request::param('kagi_language', '');
+      FreshRSS_Context::$user_conf->kagi_custom_css = Minz_Request::param('kagi_custom_css', '');
       FreshRSS_Context::$user_conf->save();
     }
   }
 
   public function addSummarizeButton(FreshRSS_Entry $entry): FreshRSS_Entry {
+    $custom_css = FreshRSS_Context::$user_conf->kagi_custom_css;
     $this->registerTranslates();
     $url_summary = Minz_Url::display(array(
       'c' => 'kagiSummarizer',
@@ -46,7 +48,8 @@ class KagiSummarizerExtension extends Minz_Extension {
       . '<a class="btn" href="' . $url_key_moments . '">'
       . _t('ext.kagiSummarizer.ui.key_moments_button') . '</a>'
       . '<p class="kagi-status hidden alert"></p>'
-      . '<blockquote class="kagi-content hidden"></blockquote></div>'
+      . '<blockquote class="kagi-content hidden" style="' . $custom_css
+      . '"></blockquote></div>'
       . $entry->content());
     return $entry;
   }
diff --git a/i18n/en/ext.php b/i18n/en/ext.php
index b701df8..c71cc1f 100644
--- a/i18n/en/ext.php
+++ b/i18n/en/ext.php
@@ -6,6 +6,8 @@ return array(
       'kagi_token' => 'Kagi Token',
       'kagi_token_help' => 'Copy and paste the "Session Link" from your <a href="https://kagi.com/settings?p=user_details" target="_blank">Kagi Account</a> settings.',
       'kagi_language' => 'Output Language',
+      'kagi_custom_css' => 'Custom CSS',
+      'kagi_custom_css_help' => 'Applied to the summary container element.',
       'lang' => array(
         'default' => 'Default',
         'bg' => 'Bulgarian',