Vertical Tab left margin no longer overridden

The update from alpha to beta1 appears to introduce an issue with the LEFT margin of vertical tabs. Basically, the left margin of 15em is no longer overwritten by claro/css/dist/components/vertical-tabs.css line 4:

.vertical-tabs{
  margin-top:0.75rem;
  margin-bottom:0.75rem;
  border-top:1px solid transparent;
}

commit: https://git.drupalcode.org/project/claro/blob/f49e9194f3cc8b91f4414a6796...

Previously, it was

.vertical-tabs {
  position: relative;
  overflow: hidden;
  margin: 10px 0;
  border: 1px solid #bdbdbd;
  border-radius: 4px;
  background: #e6e5e1;
}

See: https://git.drupalcode.org/project/claro/blob/8fb8f5dae19a25b24fec053d19...

This code overwrote this:

.vertical-tabs {
  margin: 1em 0 1em 15em; /* LTR */
  border: 1px solid #ccc;
}

found in core/misc/vertical-tabs.css.

I have also added two images to show the difference. I can override this in my child theme, but since it looks like the change also involves variables, I can't easily do a pull request.