css中怎么使用图标字体

@font-face {
  font-family: 'fontawesome';
  src: url('path-to/font-awesome.eot');
  src: url('path-to/font-awesome.eot?#iefix') format('embedded-opentype'),
       url('path-to/font-awesome.woff') format('woff'),
       url('path-to/font-awesome.ttf') format('truetype'),
       url('path-to/font-awesome.svg') format('svg');
  font-weight: normal;
  font-style: normal;
} 

body {
  font-family: 'fontawesome', sans-serif;
} 

<p>这是一个<i class="fa fa-shopping-cart"></i>购物车icon。</p> 

<link rel="stylesheet" href="path-to/font-awesome/css/font-awesome.min.css">