Adjust comment color, bit darker

Author: rtheunissen

_sass/_variables.scss

@@ -31,4 +31,4 @@ $syntax-name:       $clr-php-blue;
 $syntax-punc:       $clr-blue-grey-400;
 $syntax-class:      $clr-php-black;
 $syntax-operator:   $clr-red;
-$syntax-comment:    $clr-blue-grey-200;
+$syntax-comment:    $clr-blue-grey-400;