body
      {

        font-family: Verdana, Geneva, Tahoma, sans-serif;
        font-size: 18px;

      }

   nav
      {

        width: 200px;
        height: 100%;
        position: fixed;
        top: 0;
        left: 0;
        padding: 40px 20px;
        background-color: rgb(100, 100, 100);
        color: white;

      }

     nav ul
      {

        list-style: none;
        padding: 0;

      }

     nav a 
      {

        color: white;
        text-decoration: none;
        display: block;
        padding: 12px 4px;

      }

     nav a:hover
      {

        color: black;
        transition: 0.2s;

      }

     main
      {

        margin-left: 240px;
        
      }

     .zdroj
      {

        text-align: right;
        font-style: italic;

      }
     
     .container
      {

        max-width: 800px;

      }
      .image
      {

        max-width: 400px;
        width: 100%;

      }
      @media screen and (max-width: 768px) 
      {
        
        nav {

          width: 100%;
          height: 200px;

        }

        main
        {

          margin-top: 280px;
          margin-left: 0px;

        }

      }