anchor.diff:    ..style.border = '0'
     ..style.padding = '0'
     ..style.overflow = 'hidden';
  -  
  +
     static bool _fillByDefault = false;
  -  
  +
     static void setFillByDefault(){
       _fillByDefault = true;
     }
  -  
  -  static void setUnfillByDefault(){
  +
  +  static void setShrinkByDefault(){
       _fillByDefault = false;
     }
   
  -  final DivElement html = new DivElement()
  -  ..classes.add(CLASS);
  +  final DivElement html = new DivElement();
  +
     CssStyleDeclaration get style => html.style;
   
     Base(){
       _baseStyle.insert();
  +    addClass(CLASS);
       stage();
       if(_fillByDefault){
         fill();
  
positive.code:   void fill(){
      html.classes.add(FILL);
    }
    
    void unfill(){
      html.classes.remove(FILL);
    }
    
    void addClass(dynamic cssClass){
      if(cssClass is EnumValue){
        cssClass = cssClass.toString();
      }
      html.classes.add(cssClass);
    }
    
    void addClasses(List<dynamic> cssClasses){
      cssClasses.forEach((cssClass){
        addClass(cssClass);
      });
    }
    
    void removeClass(dynamic cssClass){
      if(cssClass is EnumValue){
        cssClass = cssClass.toString();
      }
      html.classes.remove(cssClass);
    }
    
    void removeClasses(List<dynamic> cssClasses){
      cssClasses.forEach((cssClass){
        removeClass(cssClass);
      });
    }
    
    void setSize(String width, String height, {String minWidth, String maxWidth, String minHeight, String maxHeight}){
      html.style
      ..width = width
      ..minWidth = minWidth == null? width: minWidth
      ..maxWidth = maxWidth == null? width: maxWidth
  
negative.code: part of controls_and_panels;
  
  abstract class Base{
  
    static const String CLASS = 'cnp-base';
    static const String FILL = 'cnp-fill';
    static const String CNP_STAGING_ELEMENT_ID = 'cnp-staging-element-id';
  
    static final DivElement _cnpStagingElement = new DivElement()
    ..id = CNP_STAGING_ELEMENT_ID
    ..style.position = 'absolute'
  