<style>
* {
  box-sizing: border-box;
}

body {
  font-family: Arial, Helvetica, sans-serif;
}

/* Style the header */
.headeritem {
  padding: 5px;
  text-align: center;
  font-size: 20px;
}

/* Container for flexboxes */
.rowitem {
  display: -webkit-flex;
  display: flex;
}

/* Create three equal columns that sits next to each other */
.columnitem {
  float: left;
  width: 50%;
  padding: 10px;
  vertical-align: top;
  font-size: 20px;
}


/* Clear floats after the columns */
.row:after {
  content: "";
  display: table;
  clear: both;
}

/* Style the footer */
.footeritem {
  padding: 10px;
  text-align: center;
}

/* Responsive layout - makes the three columns stack on top of each other instead of next to each other */
@media (max-width: 800px) {
  .row {
    -webkit-flex-direction: column;
    flex-direction: column;
  }
}
</style>