body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
}
header {
  background-color: #f7f7f7;
  padding: 20px;
  text-align: center;
}
.logo {
  max-width: 200px;
}
main {
  padding: 20px;
  max-width: 800px;
  margin: auto;
}
footer {
  background-color: #eee;
  text-align: center;
  padding: 20px;
  font-size: 0.9em;
  color: #555;
}
.whatsapp-button {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background-color: #25D366;
  color: white;
  padding: 15px 20px;
  border-radius: 50px;
  text-decoration: none;
  font-weight: bold;
}