自动增加编号的css工作不正常，求救

疑问解答
1

按照网上的教程，准备了css的代码：

h2::before {
  counter-increment: counter_h_2;
  content: counter(counter_h_2, cjk-ideographic) "、";

}
h3::before {
  counter-increment: counter_h_3;
  content: "（" counter(counter_h_3, cjk-ideographic) "）";
}
h4:before {
  counter-increment: counter_h_4;
  content: counter(counter_h_4, decimal) ". ";
}
h5:before {
  counter-increment: counter_h_5;
  content: counter(counter_h_2) "."
            counter(counter_h_3) "."
            counter(counter_h_4) "."
            counter(counter_h_5) ".\0000a0\0000a0";

但是对于各级标题都不起作用，每行都显示“一”完全没有自增，是怎么回事呢？

例如正文是：

<div>
  <h2>HTML</h2>
  <h2>CSS</h2>
  <h2>JS</h2>
</div>

## title1
## title2

会被渲染为：

一、HTML
一、CSS
一、JS
一、title1
一、title2

increment没有发挥作用呢？求助求助