body {
   margin: auto;
   max-width: 500px;
}

h1 {
   max-width: 500px;
   text-align: center;
   color: #fff;
   background-color:#567;
}

.mynav {
   width: 100%;
   height: 20px;
   text-align: center;
}

/* The links (buttons) in the navbar will have this style. */
.mynav a {
   text-align: center;
   padding: 14px 16px;
   color: #000;
}

img {
  max-width: 100%;
  display: block;
}