how to style scroll bar in overflow-y code example

Example: style scrollbar overflow-y

.large-2 {
  margin-left: 30px;
  float: left;
  height: 300px;
  overflow-y: scroll;
  margin-bottom: 25px;
  width: 100px;
  background: #ccc;
}

.force-overflow {
  min-height: 450px;
}

.large-2::-webkit-scrollbar-track {
  border: 1px solid #000;
  padding: 2px 0;
  background-color: #404040;
}

.large-2::-webkit-scrollbar {
  width: 10px;
}

.large-2::-webkit-scrollbar-thumb {
  border-radius: 10px;
  box-shadow: inset 0 0 6px rgba(0,0,0,.3);
  background-color: #737272;
  border: 1px solid #000;
}