ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: #333333;
  position: sticky;
}

ul li {
  float: left;
  position: sticky;
}

ul li a {
  display: block;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  position: sticky;
}

ul li a:hover {
  background-color: #111111;
  position: sticky;
}

#bar{
  position: sticky;
  top: 0;
  z-index: 10;
  padding: 10px;

}
#img{
  position: static;
  width: 100%;
  height: 5000px;
  display: block;

}
#why{
  position: absolute;
  top: 2500px;
  left: 50%;
}
#backToTop {
      position: fixed;
      bottom: 20px;
      right: 20px;
      background-color: black;
      color: white;
      padding: 10px 15px;
      text-decoration: none;
      
    }