[css-ruby] inlined annotations need to be full size

[r12a]

A.2 Inlining Ruby Annotations
https://drafts.csswg.org/css-ruby-1/#default-inline

The following represents a sample style sheet for rendering HTML and XHTML ruby markup as inline annotations:

ruby, rb, rt, rbc, rtc, rp {display: inline; white-space: inherit;
font-variant-east-asian: inherit; text-emphasis: inherit; }

I believe you also need font-size: inherit; so that the ruby annotation is the same size as the base text.

[upsuper]

I guess you would need line-height: inherit; as well.

[fantasai]

Quick fix: switch to font: inherit. ;)