message: fix styleguide color (theme-gray-subtle)
diff: @@ -59,7 +59,7 @@ export default class AppStyleguideColor extends Vue {
  'theme-darker',
  'theme-dark',
  'theme-gray',
  - 'theme-gray',
  + 'theme-gray-subtle',
  'theme-light',
  'theme-lighter',
  'theme-lightest',
  