anchor.diff:       ;
   
   innerSelector
  -    : combinatorNonWs WS* selector;
  +    : (combinatorNonWs WS*)? selector;
       
   ruleSetSelector
       : fontFaceSelector -> ^(SELECTOR fontFaceSelector)
  
positive.code:     :  MINUS? NUMBER
      ;
      
  declaration
      : (propPrefix? FONT)=>fontDeclaration
      | (property WS* COLON (WS* propertyValue (WS* important)?)? WS* SEMI
      -> ^(DECLARATION property ^(PROP_VALUE propertyValue)? important?))
      ;
  
negative.code:     ;
      
  page
      : '@' PAGE_SYM (WS+ COLON pseudoPage)? WS* LBRACE WS* (pageElement WS*)* RBRACE
      -> ^(PAGE_SYM pseudoPage? pageElement*)
      ;
  
  pseudoPage
      : ident
      ;
      
  pageElement
      : mixinSelectorList WS!* SEMI!
      | declaration
      | variableDef
      ;
  
  combinator
      : WS* combinatorNonWs WS*
      | WS+
  