[feat] <rh-footer> add font-size revert instead of px value for

[heyMP]

Description

rh-footer explicitly sets the font-size of the :host component to 18px. This was a bandaid to account for sites that had different root font-sizes.

Suggested solution

We should do this instead:

What we came up with was reverting the font-size: revert on :host will set the components base back to the users setting.  I figure we can trap door this with var(--rh-component-base-font-size, revert) or whatever

cc: @zeroedin @markcaron

[heyMP]

@zeroedin is checking on the best corse of action on this.

[bennypowers]

do we need a variable for this? Users that want to change the default should just

rh-footer {
  font-size: 25em; /* 🌶 */
}

[zeroedin]

The fix I worked in for rh-secondary-nav resets the font-size to user preference, then uses em's internally to style component sizing. I had originally used rem but spandx exposed the issue of RHDC not using user-specified font sizing.

:host {
  font-size: var(--rh-secondary-nav-base-font-size, initial);
}

This resets to initial but also allows a trap door if someone is adamant about setting that value.

As for your question @bennypowers, do we need a variable? No probably not. Your solution is more valid just override directly in light dom and skip the CSS variable.

[bennypowers]

Closed by #406