custom-furo.css

span.sidebar-brand-text {
  font-size: small;
  text-align: center;
}

div.highlight {
  background: #F4F4F4;
}

body[data-theme="dark"] div.highlight {
  background: #383838;
}

/* Copied the style for a.pdf from website/templates/index_furo.html */

a.pdf {
  margin-right: 0.5em;
}

a.pdf:hover {
  text-decoration: none;
}

/* Style for announcement banner */

.announcement {
  background: orange;
}

.announcement-content {
  color: black;
}

.announcement-content a {
  color: white;
  text-decoration: none;
}

/* Style for the floating versions menu */

.sidebar-drawer {
  z-index: 100;
}

.select-wrapper {
  display: block;
  text-align: center;
}

#versions-menu {
  display: inline-block;
  font-size: small;
  opacity: 1;
  border: none;
  background-color: transparent;
  color: var(--color-sidebar-link-text--top-level);;
}

#versions-menu:focus {
  outline: none;
}

body[data-theme="dark"] {
  #versions-menu {
    background-color: transparent;
  }
}

@media (prefers-color-scheme: dark) {
  body[data-theme="auto"] {  /* the same styles with body[data-theme="dark"] */
    #versions-menu {
      background-color: transparent;
    }
  }
}