diff --git a/core/themes/bartik/css/base/elements.css b/core/themes/bartik/css/base/elements.css
index ead25e9..4377870 100644
--- a/core/themes/bartik/css/base/elements.css
+++ b/core/themes/bartik/css/base/elements.css
@@ -35,29 +35,48 @@ h2,
 h3,
 h4,
 h5,
-h6 {
+h6,
+/**
+ * Classes '.heading-a' - '.heading-f' are not currently in use; they are still
+ * included in stylesheet to keep Seven and Bartik consistent and good examples
+ * of easy to configure base styles.
+ *
+ * @see https://www.drupal.org/node/2400233
+ */
+.heading-a,
+.heading-b,
+.heading-c,
+.heading-d,
+.heading-e,
+.heading-f {
   margin: 1.0em 0 0.5em;
   font-weight: inherit;
 }
-h1 {
+h1,
+.heading-a {
   font-size: 1.357em;
   color: #000;
 }
-h2 {
+h2,
+.heading-b {
   font-size: 1.143em;
 }
-h3 {
+h3,
+.heading-c {
   font-size: 1.092em;
 }
-h4 {
+h4,
+.heading-d {
   font-size: 1.05em;
 }
-h5 {
+h5,
+.heading-e {
   font-size: 0.889em;
   text-transform: uppercase;
   letter-spacing: 0.1em;
 }
-h6 {
+h6,
+.heading-f {
   font-size: 0.67em;
   text-transform: uppercase;
   letter-spacing: 0.1em;