#naglowek {
  width: 100%;
  height: 300px;
  background-color: yellow;
}

#lewy {
  weight: 20%;
  height: 700px;
  background-color: gray;
  float: left;
}

#środek {
  weight: 50%;
  height: 700px;
  background-color: orange;
}

#prawy {
  weight: 30%;
  height: 700px;
  background-color: gray;
}

#stopka {
  weight: 100%;
  height: 200px;
  background-color: yellow;
}