Improve contrast of text

was failing WCAG2.0 G18

styles/less/v4.0.less

@@ -425,9 +425,10 @@ pre {
 }
 
 .color-code-wrapper {
-    background-color: @faded-neutral;
+    background-color: fadeout(#000, 25);
     padding: 1em;
     margin-bottom:2em;
+    color: #fff;
     @media @bp2 {
 
     }
@@ -437,7 +438,7 @@ pre {
         font-weight: bold;
         font-size: 0.75em;
         display: block;
-        border-bottom: 2px solid @faded-neutral;
+        border-bottom: 2px solid fadeout(@cream, 75);
     }
 }