body {
  font-family: Arial, sans-serif;
  text-align: center;
  margin: 0;
  background: #fdfdfd;
}
header {
  background-color: #1a1a1a;
  color: white;
  padding: 10px;
}
nav button {
  margin: 5px;
  padding: 10px;
}
#product-img {
  width: 300px;
  height: auto;
  margin: 10px 0;
}
button {
  padding: 10px 20px;
  font-size: 16px;
}
footer {
  margin-top: 40px;
  background: #222;
  color: white;
  padding: 10px;
}