* {
  box-sizing: border-box;
}

.menu {
  float: left;
  width: 20%;
  text-align: center;
}

.menu li {
  background-color: #e5e5e5;
  padding: 8px;
  margin-top: 7px;
  display: block;
  width: 100%;
  color: black;
}

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

.right {
  background-color: #e5e5e5;
  float: left;
  width: 20%;
  padding: 15px;
  margin-top: 7px;
  text-align: center;
}

    iframe {
        width: 100%;
        margin: 13px 0px 0px 0px;
        border: none;
        font-family: sans-serif;
        height:auto;
    }

    li {
        list-style: none;
    }

@media only screen and (max-width: 620px) {
  /* For mobile phones: */
  .menu, .main, .right {
    width: 100%;
  }
}
    /* Create two equal columns that floats next to each other */
    .column {
        float: left;
        width: 25%;
        padding: 10px;
        height: auto; /*Should be removed. Only for demonstration */
        /*border-bottom: 2px solid #009952;*/
        border-top: 2px solid #009952;
    }

    /* Clear floats after the columns */
    .row:after {
        content: "";
        display: table;
        clear: both;
    }

    /* Responsive layout - makes the two columns stack on top of each other instead of next to each other */
    @media screen and (max-width: 600px) {
        .column {
            width: 100%;
        }
    }