* {
  box-sizing: border-box;
}
.menu {
  float:left;
  width:20%;
  text-align:center;
}
.menuitem {
  background-color:#e5e5e5;
  padding:8px;
  margin-top:7px;
}
.main {
  float:left;
  width:60%;
  padding:0 20px;
}
.right {
  background-color:#ffffff;
  float:left;
  width:20%;    
  text-align:center;
}


.image { max-width:100%;height:auto; }

@media only screen and (max-width:620px)
{
  /* For mobile phones: */
  .menu, .main, .right {
    width:100%;
  }
}