kzh125

OK

The rp element should be a child of ruby element, not a child of rt element

From w3schools： a small extra text

Quote

A ruby annotation is a small extra text, attached to the main text

WHATWG HTML Living Standard

and

https://www.w3schools.com/tags/tag_track.asp

https://www.w3schools.com/tags/tag_rp.asp

<ruby>
漢 <rt><rp>(</rp>ㄏㄢˋ<rp>)</rp></rt>
</ruby>

should be 

<ruby>
漢 <rp>(</rp><rt>ㄏㄢˋ</rt><rp>)</rp>
</ruby>