anchor.diff:          | Color of IColor
           | Size of ISize
           | CustomClass of string
  +        | Modifiers of IModifier list
   
       type internal Options =
           { Props : IHTMLProp list
             Color : string option
             Size : string option
  -          CustomClass : string option }
  +          CustomClass : string option
  +          Modifiers : string option list }
   
           static member Empty =
               { Props = []
                 Color = None
                 Size = None
  -              CustomClass = None }
  +              CustomClass = None
  +              Modifiers = [] }
   
       /// Generate <article class="message"></article>
       let message options children =
  
positive.code:     /// Generate <div class="message-header"></div>
      let header (options: GenericOption list) children =
          let opts = genericParse options
          let classes = Helpers.classes Classes.Header [opts.CustomClass] []
          div (classes::opts.Props) children
  
      /// Generate <div class="message-body"></div>
      let body (options: GenericOption list) children =
          let opts = genericParse options
          let classes = Helpers.classes Classes.Body [opts.CustomClass] []
          div (classes::opts.Props) children
  
negative.code:             | Option.Color color -> { result with Color = ofColor color |> Some}
              | CustomClass customClass -> { result with CustomClass = Some customClass }
              | Size size -> { result with Size = ofSize size |> Some }
              | Modifiers modifiers -> { result with Modifiers = modifiers |> parseModifiers }
  
          let opts = options |> List.fold parseOptions Options.Empty
          let classes = Helpers.classes
                          Classes.Container
                          (opts.Color::opts.CustomClass::opts.Size::opts.Modifiers)
                          [ ]
  
          article (classes::opts.Props)
  