body {
   
    margin-left: auto;
    margin-right: auto;
    width: 348px;
}

header {
    text-align: center;
}

nav {
    width: 348px;
    min-width: 348px;
}

img {
    width: 100%;
    text-align: center;
}

p {
    text-align: center;
}

footer {
  height: 40px;
  width: 348px;
  font-size: 15px;
  padding-left: 10px;
  padding-right: 10px;
  background-color: green;
}