body {
  background: url(tlo.jpg) repeat-x;
}

#strona {
  width: 900px;
  margin: auto;
}

#naglowek {
  background-color: lightblue;
  border: 5px lightblue outset;
  width: 870px;
  height: 100px;
  margin: 5px;
  padding: 5px;
  float: left;
  text-align: center;
}

#menuLewe {
  background-color: yellow;
  border: 5px yellow outset;
  width: 170px;
  height:75%;
  float: left;
  margin: 5px;
  padding: 5px;
}

#zawartosc {
  background-color: red;
  border: 5px red outset;
  width: 470px;
  height:75%;
  float: left;
  margin: 5px;
  padding: 5px;
}

#menuPrawe {
  background-color: yellow;
  border: 5px yellow outset;
  width: 170px;
  height:75%;
  float: right;
  margin: 5px;
  padding: 5px;
}

#stopka { 
  background-color: lightblue;
  border: 5px lightblue outset;
  width: 870px;
  height: 20px;
  margin: 5px;
  padding: 5px;
  float: left;
  text-align: center;
  vertical-align: center;
}