body {
  margin: 0;
  background-color: #7589ff
}

ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  width: 300px;
  background-color: #7589ff;
  position: fixed;
  height: 100%;
  overflow: auto;
}

li a {
  display: block;
  color: #000;
  padding: 8px 16px;
  text-decoration: none;
}

li a.active {
  background-color: #23294c;
  color: white;
}

li a:hover:not(.active) {
  background-color: #3f4989;
  color: white;
}