/*
  Gener8 style kit — the "Library" button (kit/js/back.js), shown in a viewer opened
  from the library. Bottom band, just right of the Gener8 mark (or in its place with
  ?logo=0), above the model but below dialogs. Sized like the other tool buttons.
*/
.g8-back {
  position: fixed; z-index: 6; bottom: var(--mark-gap, calc(var(--u) * 2.4));
  left: calc(var(--mark-gap, calc(var(--u) * 2.4)) * 2 + var(--u) * 8);
  display: flex; align-items: center; gap: calc(var(--u) * .7);
  min-height: calc(var(--u) * 5.6); padding: 0 calc(var(--u) * 1.8) 0 calc(var(--u) * 1.2);
  border-radius: 99px; font-size: calc(var(--tu) * 1.5);
}
.g8-back.nomark { left: var(--mark-gap, calc(var(--u) * 2.4)); }
.g8-back:active { transform: scale(.97); }