* {
  box-sizing: border-box;
}

.menu {
  float: left;
  width: 20%;
  text-align: center;
  border-right:1px solid gray;
}

.menu a {
  background-color: #ffffff;
  padding: 8px;
  margin-top: 7px;
  display: block;
  width: 100%;
  color: black;
}

.main {
  float: left;
  width: 60%;
  padding: 0 20px;
}

.right {
  background-color: #ffffff;
  float: left;
  width: 20%;
  padding: 5px;
  margin-top: 7px;
  text-align: center;
  border-left:1px solid gray;
}

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

a:link {background-color:#ffffff;color:black;text-decoration:none;}    /* unvisited link */
/* a:visited {background-color:#000000;color:white;text-decoration:none;}*/ /* visited link */
/* a:hover {background-color:#000000;color:white;text-decoration:none;}*/   /* hover link */
/* a:active {background-color:#ff0000;color:white;text-decoration:none;}*/  /* selected link */