leftcontent

#leftcontent {
  position: absolute;
  left:10px;
  top:50px;
  width:200px;
  background:#fff;
  border:1px solid #000;
}

testo a sx

centercontent

#centercontent {
  background:#fff;
  border:1px solid #000;
  margin-left: 201px;
  margin-right:201px;
}

testo al centro

text

text


rightcontent

#rightcontent {
  position: absolute;
  right:10px;
  top:50px;
  width:200px;
  background:#fff;
  border:1px solid #000;
}

right text

some text

some text

some text

some text

some text

some text