body {
  margin: 0;
}

header { 
  color: white;
  background-color: orangered;
  padding: 50px;
  font-size: 50px;
  text-align: left;
}

main {
  color: orangered;
  margin: 50px;
  padding: 50px;
  border: 5px solid orangered;
}
.topnav {
  background-color: #white;
  overflow: hidden;
  .topnav a {
  float: left;
  color: #black;
  text-align: center;
  padding: 20px 30px;
  text-decoration: none;
  font-size: 20px;
    .topnav a:hover {
  background-color: #black;
  color: black;
      .topnav a.active {
  background-color: #orangered;
  color: white;
}