.menu-bar .right-buttons > a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  min-height: var(--menu-bar-height);
  vertical-align: top;
}

button.chapter-fold-toggle {
  border: 0;
  background: transparent;
  color: inherit;
  font: inherit;
  min-width: 28px;
  min-height: 28px;
}

pre > code:focus-visible,
.chapter-fold-toggle:focus-visible {
  outline: 2px solid var(--links);
  outline-offset: 2px;
}