Why are the markers in a rich text field not inheriting headline styles?

Question

I'm using ordered list in the standard Rich Text field in Contentful, but when I apply the h4 or h5 in the ordered list. the 1. or the "A." does not inherit the styles of the headlines. I tried going and adding css for example this below, but this ends up applying to all "A." in the ordered list, and as you can see not every A. is a headline. What am i missing why is Contentful not inheriting the headline styles in the ordered list?

.richTextContent ol li ol li::marker {
  font-size: var(--text-size-300);
  font-weight: 600;
  color: rgb(37 37 36 / var(--tw-text-opacity));
}