header {
      background-color: navy;
      color: white;
      padding: 15px;
      text-align: center;
       }
    nav {
      background-color: darkgray;
      display: flex; }
    nav ul {
      list-style: none;
      margin: 0;
      padding: 0;
      display: flex;   
      gap: 20px;       
      }
    main {
      background-color: whitesmoke;
      color: black;
      padding: 0px;
      margin:  0px;
      }
    footer {
       background-color: darkgrey;    
       }