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                <h1><a href="#">文章标题</a></h1>
  <p>文章正文<a href="#">这是一个超链接</a></p>
  <a href="#">这是一个超链接</a>
  <h2><a href="#">二级标题</a></h2>
    <li><a href="#">列表项2</a></li>
  <h3><a href="#">三级标题</a></h3>


                /* li a, article a, p a {
	color: #000000;

h1 a, h2 a, h3 a {
  color: green;
} */

:is(li, article, p) a {
  color: #999999;

:is(h1, h2, h3) a {
  color: green;

/* 支持套娃 */
/* :is(article, p) :is(h2, li) a {
  color: #ff3344;
} */

/* 等同于 */
/* article h2 a, article li a, p h2 a, p li a {
  color: #ff3344;
} */