anchor.diff:    [W3C](https://www.w3.org) site).
     The following sections describe these selectors.
     
  -  组件样式中有一些从[影子 DOM 样式范围 (Shadow DOM style scoping)](https://www.w3.org/TR/css-scoping-1) 领域引入的特殊*选择器*：
  +  组件样式中有一些从影子(Shadow) DOM 样式范围领域（记录在[W3C](https://www.w3.org)的[CSS Scoping Module Level 1](https://www.w3.org/TR/css-scoping-1)中） 引入的特殊*选择器*：
   
     ### :host
   
  
positive.code:     If you use module bundlers like Webpack, you can also use the `styles` attribute
      to load styles from external files at build time. You could write:
  
      像 Webpack 这类模块打包器的用户可能会使用`styles`属性来在构建时从外部文件中加载样式。它们可能这样写：`styles: [require('my.component.css')]`
  
      Set the `styles` property, notthe `styleUrls` property. The module 
      bundler loads the CSS strings, not Angular. 
  
negative.code: 
    This is a big improvement in modularity compared to how CSS traditionally works.
    
    这种模块化相对于 CSS 的传统工作方式是一个巨大的改进。
    
    * You can use the CSS class names and selectors that make the most sense in the context of each component. 
    
      可以使用对每个组件最有意义的 CSS 类名和选择器。
  