*{
  margin: 0;
  padding: 0;
}

*::before, *::after {
  box-sizing: border-box;
}

ul {
  list-style: none;
}

.header {
  height: 50px;
  background-color: aquamarine;
  color: #fff;
  font-size: 32px;
  text-align: center;
}

.footer {
  position: absolute;
  bottom: 0;
  height: 50px;
  text-align: center;
  font-size: 32px;
  background-color: aqua;
  left: 0;
  right: 0;
  color: #fff;
}

#scroll-container {
  position: absolute;
  width: 100%;
}

.container {
  position: absolute;
  top: 50px;
  bottom: 50px;
  overflow: auto;
  z-index: -1;
  width: 100%;
}

.container ul li {
  height: 100px;
  line-height: 100px;
  border-bottom: 1px solid orchid;
  box-sizing: border-box;
  text-align: center;
  position: absolute;
  width: 100%;
}

.scroll-container::-webkit-scrollbar {
  background-color: orchid;
  width: 2px;
}

.scroll-container::-webkit-scrollbar-thumb {
  background-color: red;
}

/* .scroll-container::-webkit-scrollbar-track {
} */