body {
  margin: 0; 
  padding: 0;
  background: #e4e9ec;
}

#container1 {
  width: 900px;
}

#container2 {
  width: 900px;
}

#container3 {
  width: 900px;
}

#content {
  background: red;
  margin: 0 5px 0 5px;
  min-height: 1050px;
}

#menu {
  margin: 50px auto;
  border:1px solid #000000;
}