diff --git a/.stylelintrc b/.stylelintrc
index ede0ce30d7df5f7fb510dd3d58078cbedafd17c0..b21f43efccf2ee277902e6728480af726843c3e9 100644
--- a/.stylelintrc
+++ b/.stylelintrc
@@ -6,5 +6,13 @@
      "ee/app/assets/stylesheets/startup/startup-*.scss",
      "app/assets/stylesheets/highlight/themes/*.scss",
      "app/assets/stylesheets/lazy_bundles/cropper.css"
+   ],
+   "overrides": [
+    {
+      "files": ["app/assets/stylesheets/mailer.scss"],
+      "rules": {
+        "color-hex-length": "long"
+      }
+    }
    ]
 }
diff --git a/app/assets/stylesheets/mailer.scss b/app/assets/stylesheets/mailer.scss
index f17baea4dd23d3cdd08e5108896cb4f5c8c1718b..f37fdf05c7b8c2300638a6d5f8cdc0afdcd4d22a 100644
--- a/app/assets/stylesheets/mailer.scss
+++ b/app/assets/stylesheets/mailer.scss
@@ -3,12 +3,12 @@
 // Do not use 3-letter hex codes, bgcolor vs css background-color is problematic in emails
 //
 $mailer-font: 'Helvetica Neue', Helvetica, Arial, sans-serif;
-$mailer-text-color: #333;
+$mailer-text-color: #333333;
 $mailer-bg-color: #fafafa;
 $mailer-link-color: #3777b0;
-$mailer-link-muted-color: #333;
+$mailer-link-muted-color: #333333;
 $mailer-line-cell-bg-color: #6b4fbb;
-$mailer-wrapper-cell-bg-color: #fff;
+$mailer-wrapper-cell-bg-color: #ffffff;
 $mailer-wrapper-cell-border-color: #ededed;
 $mailer-header-footer-text-color: #5c5c5c;
 $full-width: 640px;