.box{
  border: 4px dashed rgba(0,0,0,.2);
  margin: 5px;
  padding: 10px;
}

h2{
  font-size: 30px;
}


.box-1{
  background-color: yellow;
}

.box-2{
  background-color: blue;
  color: white;
  position: sticky;
  top: 0;
  bottom :0;
}

.box-2:after{
  content: 'watch me stick!';
}

.box-3 {
  background-color: pink;
}

.box-4 {
  background-color: red;
}

.box-5 {
  background-color: violet;
}

.box-6 {
  background-color: orange;
}

.box-7 {
  background-color: pink;
}