Rendered font size for 4th Markdown identation is too small

[cason]

Example: https://docs.cometbft.com/main/spec/abci/abci++_methods#parameters-and-types

The title of the sub-sub-sub-section Parameters and Types is rendered with a font which is even smaller than the regular font, for non formatted text.

The example above is rendered from this page: https://github.com/cometbft/cometbft/blob/main/spec/abci/abci%2B%2B_methods.md#parameters-and-types. While it is true that is small also on Github, it is not smaller than the regular font.