body 
{ 
  background-color: #ffffff;
  margin-top: 20px;
  margin-bottom: 20px;
  margin-left: 20px;
  margin-right: 0px;
  padding-left: 0px;
  padding-right: 0px;
}

#menu {
  top: 520px;
  width: 500px;
  height: 20px;
  background-color: #cccccc;
  padding-left: 2px;
}
#main {
  top: 540px;
  width: 500px;
  height: 500px;
  background-color: #ffffff;
  padding-left: 2px;
  padding-right:2px;
}
#bottom {
  bottom: 5px;
  width: 500px;
  height: 20px;
  background-color: #cccccc;
  padding-left: 2px;
  padding-right: 2px;
}