jku-se-react/src/App.css

#wrapper{
  width: 30%;
  max-height: 80vh;
  overflow: hidden;
}
.person {
  background-color: #ddd;
  color: #444;
  cursor: pointer;
  padding: 18px;
  width: 100%;
  border: none;
  text-align: left;
  outline: none;
  font-size: 15px;
  transition: 0.4s;
}

#offline .person{
  background-color: #eee;
}

#offline .person:hover, #online .person:hover {
  background-color: #bbb;
}

.extend {
  padding: 0 18px;
  display: none;
  overflow: hidden;
}

img{
  width: 90px;
  float: left;
  margin-right: 20px;
  margin-top: 10px;
}

#wrapper{
  float: left;
}

.mapWrapper{
  float: right;
}