http://appro.mit.jyu.fi/opetusteknologia/luennot/luento4/asemointi.css

.base {
  height: 50%;
  width: 50%;
  position: absolute;
  color: #515151;
  background-color: #e1e1e1;
  top: 25%;
  left: 25%;
  z-index: 10;
}

.absolute {
  position: absolute;
  top: 10%;
  right: 10%;
  width: 40%;
  height: 40%;
  color: #515151;
  background-color: #d1d1d1;
}

.fixed {
  position: fixed;
  bottom: 0%;
  right: 0%;
  width: 20%;
  height: 20%;
  color: #515151;
  background-color: #d1d1d1;
  z-index: 5;
}

.fixed2 {
  position: fixed;
  top: 0%;
  left: 0%;
  width: 20%;
  height: 20%;
  color: #515151;
  background-color: #d1d1d1;
}