body {
  margin: 0;
  background: #000;
  color: #fff;
  font-family: Arial, sans-serif;
}
.container {
  padding: 20px;
  max-width: 600px;
  margin: auto;
}
h1 {
  font-size: 2em;
  text-align: center;
  margin-bottom: 1em;
}
p {
  font-size: 1.2em;
  text-align: center;
}
@media (min-width: 768px) {
  h1 { font-size: 2.5em; }
  p { font-size: 1.5em; }
}