.parent {
  width: 300px;
  height: 40vh;
  overflow-y: scroll;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.parent::-webkit-scrollbar {
  display: none;
}
/*设置的子盒子高度大于父盒子，产生溢出效果*/
.child {
  height: auto;
}

.child li {
  height: 50px;
  margin: 2px 0;
  background: #009678;
}
