add view helper for mail heading

app/helpers/emails_helper.rb

@@ -66,4 +66,17 @@ module EmailsHelper
       )
     end
   end
+
+  def email_default_heading(text)
+    content_tag :h1, text, style: [
+      "font-family:'Helvetica Neue',Helvetica,Arial,sans-serif",
+      'color:#333333',
+      'font-size:18px',
+      'font-weight:400',
+      'line-height:1.4',
+      'padding:0',
+      'margin:0',
+      'text-align:center'
+    ].join(';')
+  end
 end