#sectionIndex {
  position: fixed;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 9999;
  font-family: sans-serif;
}

#sectionIndex ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

#sectionIndex li {
  width: 16px;
  height: 16px;
  margin: 12px 0;
  border-radius: 50%;
  background: rgba(255,255,255,0.3);
  cursor: pointer;
  position: relative;
  transition: all 0.3s ease;
}

#sectionIndex li.active {
  background: #fff;
  box-shadow: 0 0 8px #00ffff, 0 0 12px #00ffff inset;
}

#sectionIndex li:hover::after {
  content: attr(title);
  position: absolute;
  right: 30px;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(0,0,0,0.75);
  color: #fff;
  padding: 4px 8px;
  border-radius: 4px;
  white-space: nowrap;
  font-size: 0.8rem;
  pointer-events: none;
}