#mainblock {
  width: 500px;
  margin-left: 0px;
  margin-right: 0px;
  margin-top: 5px;
  float:left;
  text-align: center;
  height: 390px;
}

#sep {
background-color:rgb(235,235,235);
width: 1px;
margin-top: 0px;
height: 340px;
margin-bottom: 15px;
float:left;
}

#rightblock {
  width: 310px;
  margin-left: 0px;
  margin-top: 5px;
  text-align: left;
  float:left;
}