How to close a tag using regular expressions?

Question

Automation

There is an HTML code

<span class=rvts6>Заголовок</span>
<span class=rvts8>Текст</span>

how to compose a regular expression so that
<span class=rvts6>Заголовок</span>it becomes <h1>Заголовок</h1>
, but <span class=rvts8>Текст</span>it becomes <p>Текст</p>
Perhaps there is some way besides regular expressions.
I tried deleting everything </span>, then closing the tags through HTML Tidy - it more or less works, but is not friendly with Cyrillic when running multiple times through macros