body {
    background-color: ghostwhite;
}
h1 {
    color: black;
    text-align: center;
}

h2 {
    color: black;
    text-align: center;
}
      
h3 {
    color: black;
    text-align: left;
}
      
li {
    color: black;
    text-align: left;
}


<style>
body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
}

.topnav {
  overflow: hidden;
  background-color: #333;
}

.topnav a {
  float: left;
  color: #f2f2f2;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  font-size: 17px;
}

.topnav a:hover {
  background-color: #ddd;
  color: black;
}

.topnav a.active {
  background-color: #8b3288;
  color: white;
}
</style>