aside{
  position: fixed;
  left: 20px;
  top: calc(50% - 130px);
}
aside ul{
   
}
aside ul li:not(:last-child){
  margin-bottom: 20px;
}
aside ul li a{
  font-size: 0;
  width: 10px;
  height: 10px;
  display: block;
  background-color: #ccc;
  border-radius: 50%;
  transition: 0.5s;
}
aside ul li a:hover{
  background-color: #073683;
}
.currentB{
  font-size: 18px;
  background-color: transparent;
}