HTML 标签：`h1`, `h2`, `h3`, `h4`, `h5`, 和 `h6`

分级的标题，h1 是顶级标题，h6 是最低级标题。

可选属性

示例


<h1>The Main Heading</h1>
<!-- stuff -->

<section>
    <h2>A Subheading</h2>
    <!-- sub-stuff -->
</section>

<section>
    <h2>Another Subheading</h2>
    <!-- sub-stuff -->

    <h3>A Subheading of a Subheading</h3>
    <!-- sub-sub stuff -->
</section>