anchor.diff:      we generally prefer the [NgClass directive](#ngClass) for managing multiple class names at the same time.
   
   :marked
  -  ### Style binding
  +  ### Style Binding
   
     We can set inline styles with a **style binding**.
   
  
positive.code: 
  .l-main-section
  :marked
    ## Event binding
    The bindings we’ve met so far flow data in one direction: *from the component to an element*.
  
    Users don’t just stare at the screen. They enter text into input boxes. They pick items from lists.
  
negative.code: 
    <a id="eventemitter"></a>
    <a id="custom-event"></a>
    ### Custom Events with EventEmitter
  
    Directives typically raise custom events with an Angular [EventEmitter](../api/core/index/EventEmitter-class.html).
    A directive creates an `EventEmitter` and exposes it as a property.
  