对部分和子部分进行编号（比如 "Section 1"、"1.1"、"1.2"）的方法 - 在线编辑器

          <!DOCTYPE html>
<html>
<head>
  <style>
    body {
      counter-reset: section;
    }

    h1 {
      counter-reset: subsection;
    }

    h1:before {
      counter-increment: section;
      content: "Section " counter(section) ". ";
    }

    h2:before {
      counter-increment: subsection;
      content: counter(section) "." counter(subsection) " ";
    }
  </style>
</head>

<body>

  <p><b>注意:</b> 仅当 !DOCTYPE已经定义 IE8支持 这个属性.</p>

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</body>
</html>
        